  AGRICULTURAL ENGINES. The late Mrs. Trevithick said "that during the difficulties in London in 1808 and 1810, when Trevithick was overwhelming himself with new experiments and the cost of patents, and law expenses, lawyers and bailiffs took everything worth having from her house, including account-books, drawings, papers, and models, which she never saw again." His earlier account-books left in safety in his Cornish home, though very disconnected, give trustworthy traces of his work up to 1803. From that time only detached accounts or papers are found until 1812, when the unused pages in two old mine account-books of his father served as his letter (rough-draft) books; and judging from their number and style, his correspondence was most extensive and varied. [Rough draft.] "To Sir Christopher Hawkins, Baronet. Sir I now send you, agreeable to your request, a plan and description of my patent steam-engine, which I lately erected on your farm for working a thrashing mill. The steam-engine is equal in power to four horses, having a cylinder of 9 inches in diameter. The cylinder, with a moderate heat in the boiler, makes thirty strokes in a minute, and as many revolutions of the fly-wheel, to every one of which the drum of the thrashing mill (which is 3 feet in diameter) is turned twelve Trevithick's High-pressure Steam-puffer Thrashing Engine Trevithick's High-pressure Steam-puffer Thrashing Engine, 1812. "The expense of your engine of 4-horse power, compared with the expense of four horses, is as follows:—
"Two bushels or 164 lbs. of coal will do the work of four horses, costing 2s. 6d. "Four horses at 5s. each, gives 20s. Cost of coal, 2s. 6d. as compared with 20s. for horses. "I remain, Sir, "Having been requested to witness and report on the effect of steam applied to work a mill for thrashing corn at Trewithen, we hereby certify that a fire was lighted under the boiler of the engine five minutes after eight o'clock, and at twenty-five minutes after nine the thrashing mill began to work, in which time 1 bushel of coal was consumed. That from the time the mill began to work to two minutes after two o'clock, being four hours and three-quarters, 1500 sheaves of barley were thrashed clean, and 1 bushel of coal more was consumed. We think there was sufficient steam remaining in the boiler to have thrashed from 50 to 100 sheaves more barley, and the water in the boiler was by no means exhausted. We had the satisfaction to observe that a common labourer regulated the thrashing mill, and in a moment of time made it go faster, slower, or entirely to cease working. We approve of the steadiness and the velocity with which the machine worked; and in every respect we prefer the power of steam, as here applied, to that of horses. This first high-pressure steam thrashing machine was working on the 13th February, 1812, at Trewithen, the property of Sir Christopher Hawkins, as proved by Trevithick's drawing of the machine, his account of the work performed, and the report of the three wise men that the power of steam was preferable to the power of horses. Its first cost was less than that of a horse machine; but to make the calculated amounts come The whole design evidences simplicity and consequent cheapness; no complication of valves or valve-gear, no cylinder cover, parallel motion, guide-rods, or air-pump, with its condenser and injection-water. The 4-horse engine, with boiler complete, cost 90l. A common labourer worked it, and as it needed no supply of feed-water during six hours of work, the cost and attention of supplying feed were avoided. If a supply was required during the day it could be given by a pipe with two taps. This first use of steam in agriculture was immediately followed by Lord Dedunstanville of Tehidy, Mr. Kendal of Padstow, and Mr. Jasper of Bridgenorth. Sir Charles' request for a more official report signed by disinterested persons brought a reply that the thrashing engine continued to work well. "It far exceeds my expectation. I am now building a portable steam-whim, on the same plan, to go itself from shaft to shaft." "If you should fall in with any West India planter that stands in want of an engine, he may see this at work in a month, which will prove to him the advantage of a portable engine to travel from one plantation to another. The price complete is 105l." "Dear Sir, "I am sorry it is not convenient for me to advance you the money for Wheal Liberty; adventurers having the dues very low, ought to furnish the needful. I am very glad you have "By the enclosed letter, Sir John Sinclair wishes you to send him an account of your improved steam-engines. You will be careful in drawing up your letter to Sir John, because it will probably be read to the Board of Agriculture, and perhaps inserted in their publication. You will begin by acknowledging his letter, of date ... respecting the American passage boat ... and your improved small steam-engine. You will give him an account of the saving you have effected at Dolcoath, and a certificate of the same by the mining captains; the engine for thrashing you built for me, and the work it did, and the coals it consumed; the expense of the steam-engines, and the uses they may be applied to. "I remain, dear Sir, In 1812 Trevithick advertised the use and sale of steam-engines, weighing 15 cwt., costing 63l., for thrashing, grinding, sawing, or other home work; and also a more powerful engine for the steam-plough, or the harrow and spade machine for 105l., to travel from farm to farm. He wrote to Sir John Sinclair: "I received from Sir Charles Hawkins a copy of Dr. Logan's letter to you, also a note from you to Sir Charles Hawkins, both respecting the driving boats by steam; respecting the "The steam may be raised, and the engine moved a distance of two miles, and the thrashing machine at work, within one hour. "The weight, including engine, carriage, and wheels, will not exceed 15 cwt.; about the weight of an empty one-horse cart. "The size is 3 feet diameter, and 6 feet high. If you wish to have one of this size sent to the Board of Agriculture as a specimen, the price delivered in London will be sixty guineas." This engine differed from that referred to in the drawing of Sir Charles Hawkins, mainly in the boiler having the fire-place in the fire-tube, requiring no brickwork, and having the advantage of portability. It was very like the earlier locomotive boiler, except that it was placed upright, as steam-cranes now use boilers, instead of being horizontal. [Rough draft.] "To Sir John Sinclair. "I have your favour of the 4th instant, informing me that you had sent my letter respecting propelling ships by steam to the Navy Board; and also requesting a drawing and statement of the thrashing engine to be sent to the President of the Board of Agriculture, which shall be forwarded immediately. "I beg to trouble you with a few wild ideas of mine, which perhaps may some future day benefit the public, but at this time remain buried, for want of encouragement to carry it into execution. "The average consumption of coals in large steam-engines is "The average cost of this coal in the kingdom is sixpence. The average of a horse's labour for one day is about 4000 tons lifted 1 foot high, costing about 5s. "A man's labour for one day is about 500 tons lifted 1 foot high, costing 3s. 6d. "I have had repeated trials of the water lifted by coals, horses, and men, proving that where a bushel of coal can be purchased for sixpence, that sixpence is equal to 20s. of horse labour, and to 3l. 10s. of men's labour. "If you calculate a man to lift 500 tons 1 foot high, it is equal to 100 tons lifted 5 feet high; a very hard task for a man to perform in a day's work. "This calculation proves the great advantage of elemental power over animal power, which latter I believe can in a great part be dispensed with if properly attended to, especially as we have an inexhaustible quantity of coals. "To prove to you that my ideas are not mere ideas, in general my wild ideas lead to theory, and theory leads to practice, and then follows the result, which sometimes proves of essential service to the public. "About six years ago I turned my thoughts to this subject, and made a travelling steam-engine at my own expense to try the experiment. "I chained four waggons to the engine, each loaded with 2½ tons of iron, besides seventy men riding on the waggons, making altogether about 25 tons, and drew it on the road from Merthyr to the Quaker's-yard (in South Wales), a distance of 9¾ miles, at the rate of four miles per hour, without the assistance of either man or beast, and then, without the load, drove the engine on the road sixteen miles per hour. "I thought this experiment would show to the public quite enough to recommend its general use; but though promising to be of so much consequence, has so far remained buried, which discourages me from again trying, at my own expense, for the public, especially when my family call for the whole of my receipts from my mining concerns for their maintenance. "It is my opinion that every part of agriculture might be performed by steam; carrying manure for the land, ploughing, harrowing, sowing, reaping, thrashing, and grinding; and all by the same machine, however large the estate. "Even extensive commons might be tilled and effectually managed by a very few labourers, without the use of cattle. "Two men would be sufficient to manage an engine, capable of performing the work of 100 horses every twenty-four hours; requiring no extensive buildings or preparations for labourers or cattle, and having such immense power in one machine as could perform every part in its proper season, without trusting to labourers. "I think a machine that would be equal to the power of 100 horses would cost about 500l. "My labour in invention I would readily give to the public, if by a subscription such a machine could be accomplished and be made useful. "It would double the population of this kingdom, for a great part of man's food now goes to horses, which would then be dispensed with, and so prevent importation of corn, and at a trifling expense make our markets the cheapest in the whole world; because there are scarcely any coals to be found except in England, where the extreme price, duty included, does not exceed 2s. per bushel. "I beg your pardon for having troubled you with such a wild idea, and so distant from being carried into execution; but having already made the experiment before stated, which was carried out in the presence of above 10,000 spectators, who will vouch for the facts, I venture to write to you on the subject, for the first and only self-moving machine that ever was made to travel on a road, with 25 tons, at four miles per hour, and completely manageable by only one man, I think ought not to be dropped without further experiments, as the main point is already obtained, which is the power and its management. "Your most obedient servant, The Board of Agriculture in 1812 had their attention drawn to the feasibility of using the steam-engine to save agricultural labour and lessen the cost of working land. Trevithick's intuitive knowledge told him his application would be in vain, though an engine was at work proving the saving of horse-power in the item of thrashing corn. "I beg to trouble you with a few wild ideas of mine, which perhaps may some future day benefit the public." A steam-engine could exert as much power by the consumption of 6d. worth of coal as could be given by 20s. of horse-power, or by 70s. worth of men's power. "Ideas lead to theory, theory leads to practice, then follows the result, which sometimes proves of essential service to the public." "It is my opinion that every part of agriculture might be performed by steam. Carrying manure for the land, ploughing, harrowing, sowing, reaping, thrashing, and grinding; and all by the same machine, however large the estate." "Two men would manage an engine capable of performing the work of 100 horses." Such a use of the steam-engine, judiciously managed, "would double the population of this kingdom, and make our markets the cheapest in the world; because England is the country best supplied with coal and iron for steam-engines, and the land now growing food for horses would be available for man." Its cost would be 500l., and its power sufficient to propel the largest subsoil ploughs and tormentors; and had the Board of Agriculture supplied such a sum of money as is now ordinarily given by a farmer for a steam-plough, we should have had in 1812 ploughing, harrowing, sowing, reaping, &c., by steam. Years [Rough draft.] "Sir Charles Hawkins, Bart., "Sir,—I have your favour of the 27th April, respecting a steam-engine for your friend for the West Indies, of the power of ten mules employed at one time. This power we calculate equal to forty mules every twenty-four hours, as six hours' hard labour is sufficient for one mule for one day. "The expense of an engine of this power complete delivered in London would be 200l. The consumption of coals about 84 lbs., or one bushel, to equal the labour of three mules, or from 13 to 14 bushels of coal every twenty-four hours to perform the full work of forty mules (or in proportion for a lesser number), with a waste of about 15 gallons of water per hour, unless a reservoir was made to receive the steam, and then to work the same water over again. "Where water is scarce, nearly the whole may be saved. "You remarked that the rope might slip round the notch in the wheel; but to prevent any risk of that kind, I apply a small chain instead of the rope, which works the same as a chain on the barrel of a common thirty-hour clock. "The speed of the periphery of the fly-wheel is about eight miles per hour, which I think is nearly double the speed of the mules when at work in the mill. This would reduce the size of the part which carries the chain on the cattle mill to half the diameter of the present walk of the cattle, which might be done without altering or interfering with the present cattle mills, and might, if required, either work separately or "To inform your friend of the power and effect of such an engine, I prefer his sending some person down to Cornwall, to see it tried on some of the cattle mills or whims in the mines. "Engines that have been sent to the West Indies hitherto have cost nearer 2000l.; very large, heavy, and complicated machines, requiring 2500 gallons of water per hour for condensing, and could only be managed by a professed engineer, while any common labourer can keep in order and work these engines. If you prefer to send a person with it, the cost will be about 40s. per week. "I remain, Sir, "Richard Trevithick." This letter indirectly points out two long-standing radical errors in engineering phraseology. An early method of describing the value of an engine was by stating the number of pounds it would lift one foot high by the burning a bushel of coal, called the duty of an engine. Trevithick's bushel was 84 lbs., while other engineers, under the same term of bushel, meant various weights, up to 120 lbs. Another form of speaking was the horse-power of an engine; meaning that a horse could lift a certain number of pounds one foot high in a minute, and that a steam-engine lifting ten times as much was a 10-horse engine; but, as Trevithick points out, a horse only works at that rate for six hours out of twenty-four, while the steam-engine works continuously, performing the work of forty horses, yet is called a 10-horse engine. The high-pressure engine suitable for the West Indies was to be adapted to the existing horse or mule [Rough draft.] "Sir Charles Hawkins, Bart., "Sir,—Yours of the 15th of last month I received, enclosing a drawing of a sugar-mill from Mr. Trecothick, which I should have answered per return, but was at that time in treaty for an engine for a sugar-mill with a Mr. Pickwood, who is in St. Kitts in the West Indies. "The engine is now being erected at Hayle Foundry, of the power of twelve mules at a time, or equal to forty-eight mules during twenty-four hours. "The cost is 210l. complete, with numerous duplicate parts. "I hope she will be finished and sent off in a short time. "I have now so fully proved the use of those engines, that I have engaged to take this one back if it does not answer their purpose, and to refund the whole sum if they return the engine to me in working order within four years. "This gentleman says, if this engine answers he shall have two more for his own use, and four of his friends are waiting to see the result before ordering their engines. "The mules that will be turned out of use by Mr. Pickwood's engine will sell for five times the sum the engine will cost him, exclusive of the wear of mules, with their keep and drivers, besides the greater dispatch and pleasantness of working a machine instead of forcing animals in so hot a climate. "If your friend wishes an engine of this power and on the same terms, I can get two made and sent to London nearly in the same time as one. Enclosed I send to you a rough sketch of the engine and mill. I am of your opinion, that Sir John Sinclair has taken a useless journey by calling on the Navy Board, for nothing experimental will ever be tried or carried into effect except by individuals. "If I could get an Act of Parliament for twenty-one years for only one-tenth part of the saving which I could gain over animal power and expense, I have no doubt but that I could get "But a patent is but for fourteen years, and open to constant infringement; for the inventor of general and useful machinery is a target for every mechanic to shoot at, and unless protected or encouraged by some better plan than a common patent, will have the whole kingdom to contend with in law, and most likely receive ruin for his reward, which has too often been the case. "A plan of such magnitude as this promises to be of, I think ought to be carried into effect by subscription, and as soon as accomplished, the subscribers to be repaid, and the invention thrown open for the use of the kingdom at large. I think about 1000l. or 1500l. would test the designs. "It is expected that Mr. Praed will spend some time in this neighbourhood; I hope I shall be able to prove to you and to him the great use of propelling barges by steam. I have a small engine now at foundry, and would put it on board one of their barges for your inspection. I am very much obliged for your continued favours, and beg pardon for so often troubling you. I have so fully proved the great advantages resulting from those portable engines, that I very much wish the public to have the full use of them. "I remain, Sir, A 12-mule-power engine for St. Kitts was being erected at Harvey's foundry at Hayle; Trevithick making himself liable for the whole cost, in case it should not answer the purpose. The mules thrown out of work by the engine would sell for five times as much as the engine cost, to say nothing of the saving in wear and tear of drivers and mules, and the unpleasantness of driving a mule in hot weather as compared with a machine. If an Act of Parliament would give him one-tenth of the saving he could effect during twenty-one years, a company might be formed for carrying into full effect his plans for propelling ships, travelling with weights on roads, and performing almost every kind of agricultural labour, while a patent for fourteen years was open to constant infringement, and the inventor of useful machinery was a target for every mechanic to shoot at, had law suits with the kingdom at large, and ultimate ruin, as a reward for his labours. Inventions of such general application, when fairly established, should be thrown open to the public, Government paying the inventors their expenses, and reasonable reward for their time. [Rough draft.] "Mr. Pickwood, "Sir,—Yours of the 17th April I received about twenty days since, and from that time to the present have been in treaty with Messrs. Plummer, Barham, and Co., for your engine. We have now closed for an engine complete, of the power of twelve mules at a time, with suitable duplicates, chains, &c., for 210l. I very much wish for your engine to be set to work by your own workmen, to show the planters the simplicity and easy management of the machine, and also save the expense of an engineer, which will tend to promote their use. The engine will be set to work before it is sent off, and every possible care taken to execute it in the most perfect order. From the experience I have had with common labourers keeping these engines in order, since I wrote to you, I have no doubt you will get on satisfactorily. "I hope to get the engine ready in five or six weeks, but I fear there will be loss of time in shipping it. You may rest assured that I will spare no time or attention to promote the performance of this engine. I am so far satisfied with the probability of its fully answering your purpose that I voluntarily offered Messrs. Plummer, Barham, and Co., that if you return it "Enclosed I send you a sketch of the engine attached to a sugar-mill. Please write to me by return of the packet; it may be in time, before the engine is shipped, to alter, or send you such things as I may not be acquainted with. I shall be glad to know the number of yards your mules travel in an hour when going at what you call a fair speed, in the mill, and also what number of rounds you wish the centre roll to make in an hour when worked by the engine. "I remain, Sir, "R. W. Pickwood, Esq., These are not the remarks of an uncertain schemer; every sentence having the impress of the ability and fixed intention of perfecting the work, and the belief that the simplicity of the engine would enable a common labourer to use it. [Rough draft.] "Sir Ch. Hawkins, Bart., "Sir,—If your friend Mr. Trecothick intends to have a sugar-mill engine immediately finished and sent out with the one I am now making for Mr. Pickwood, he ought not to lose any time in giving his orders. I have made inquiry at Falmouth about sending out Mr. Pickwood's engine for St. Kitts on board a packet, which would save much time, but I fear it cannot be granted unless application is made by some person of note to the Post Office in London. Mr. Banfield of Falmouth told me that if application was made to send out a model as a trial, he had no doubt but it would be granted. "This experiment with the portable engine that will travel from one plantation to another and work without condensing water, is certainly of the greatest consequence to the planters, "I remain, Sir, This experiment with the 1¾ ton portable engine to travel from one plantation to another, needing no condensing water, was certainly of the greatest consequence to the planters in the West Indies, and should have been of equal importance to the people in England. Judging from the weight and cost, as compared with agricultural engines of the present day, Trevithick was nearer the mark then than we are now; its working without condensing water the engineers of that day believed to be impracticable, a fundamental error which greatly retarded the use of the high-pressure steam-engine. The providing sufficient condensing water was often a most serious item of cost, and as water mains were not in use, a deep well was a necessary part of a steam vacuum engine. [Rough draft.] "Gentlemen, "Yours of the 30th of September I found at my house on my return yesterday from a journey. I am sorry to inform you that Mr. Pickwood's engine is not ready. Near three months ago I set my smiths and boiler-makers to work to complete an engine for Mr. Pickwood, which parts were finished five or six weeks ago. The other parts of the engine, which were to have been made of cast iron, were ordered and commenced at a foundry in this county, belonging to Blewett, "I remain, Sir, "Messrs. Plummer, Barham, and Co., "P.S.—Immediately on my receiving your order to prepare an engine for Mr. Pickwood I wrote to inform him that I had begun it, and enclosed a drawing of the engine with the method of connecting the engine to the cattle-mills, and requested he would remit to me his remarks on it, which I received by the last packet, from which it appears for the best that the engine is not in a forward state, because the parts would not have been so suitable to the purpose as they will now be." Fortune was against Trevithick. A difficulty between his brother-in-law Harvey, and his old partner Vivian, with Blewett, retarded the completion of the engine; and the castings so anxiously waited for were ordered from Hazeldine and Rastrick. The wrought-iron work was made by the old smiths in his neighbourhood, who had long been in the habit of hammering his schemes into shape. This patchwork way of constructing engines made success much more difficult. Trevithick often laughed heartily at the following incident which occurred during this quarrel at Harvey's works:—Blewett sent a handsome silver teapot to Miss Betsy Harvey, who kept her brother's house, The following was written to Mr. Rastrick in December, 1812: "I have been waiting your answer to my last, and especially that part respecting the West India engine, as there is a large field there for engines of this kind. I have received an order for a thrashing engine for Lord de Dunstanville of Tehidy, and as I wish those thrashing engines to be known through the country, I intend to take one of the engines ordered for Padstow and send it to Tehidy; one of the Padstow farmers can wait until you make another for him; therefore I would thank you to send the first finished by ship from Bristol for Portreath or Hayle. Send a drum with everything complete, of which you are a better judge than I; probably about 3 feet in diameter and 3½ feet long will be sufficient. There must be a fly-wheel, with a notch to carry the rope, and also a small notch wheel on the drum-axle. I think 6½ feet diameter for the fly and 9½ inches diameter for the small wheel, will give speed enough to the drum. Mind to cast a lump or screw on a balance of about 1 cwt. on one side of the wheel. There must be two stands on the boiler, and a crank-axle or otherwise a crank-pin in the fly-wheel, whichever you please; with a shaft 3 feet long with a carriage. The engine to stand in a room under the turn-about, 7½ feet high, 7 feet wide, and 17 feet "I send you a sketch showing how it is to stand. I do not bind you to the size of the drum or wheels, only the room that the fly-wheel works in is but 7 feet wide. Put the engine and drum for Lord de Dunstanville out of hand neat and well, as it will be well paid for, and make the stands, &c., in your own way." This description of Lord Dedunstanville's thrashing machine illustrates the drawing of that supplied to Sir Charles Hawkins. [Rough draft.] "Mr. Rastrick, "Sir,—I have your favour of the 10th inst., in which you do not state the time when you expect I shall have either of the engines that you are executing. As so much time has elapsed since the orders were given, the persons that ordered them are quite impotent. The ploughing engine that I sent you a drawing for, after being tried for that purpose, was to have been sent to Exeter for pumping water out of the foundations of a new bridge; but as they intend to begin their work at the bridge before the end of March, the engine must be there before that time, or they will erect horse machines and not use the engine. I have therefore been obliged to send the small boiler that I had for that purpose to Hayle Foundry, and get the castings made there for this engine to get it in time to prevent losing the order. I have also been obliged to take the small portable engine from Wheal Alfred Mine and have new apparatus fitted to it, to apply this engine for Plymouth Breakwater. A small engine, from the same patterns as Sir Charles Hawkins' thrashing engine, which I had at work in a mine, I "That new engine you saw near the seaside with me is now lifting forty millions 1 foot high with 1 bushel of coal, which is very nearly double the duty that is done by any other engine in the county. A few days since I altered a 64-inch cylinder engine at Wheal Alfred to the same plan, and I think she will do equally as much duty. I have a notice to attend a mine meeting to erect a new engine equal in power to a 63-inch cylinder single, which I hope to be able to send to you for. I have also an appointment to meet some gentlemen at Swansea, to erect two engines for them, one to lift water, the other coal, which you will hear more about, I expect, soon. If I can spare a few days when at Swansea, I will call to see you at Bridgenorth. I have not seen Mr. Richard since you left, but will call on him in a few days and do as you request. If you think the fly-wheel "If you cannot finish all these engines at the same time, I would rather the smaller ones should be finished first and Mr. Richards' stand a little, because if his engine was now ready he would not pull down his thrashing machine until he had nearly thrashed all his corn, and the machine now stands on the spot where the mill is to be erected. "If I call on you from Swansea I think I shall be able to show you a new idea, which I think will, if carried into practice, be of immense value. Please to write to me and say particularly how you are getting on, and when you are likely to finish the engines ordered. Trevithick had sent a drawing of a ploughing engine to Rastrick at Bridgenorth, that the castings might be made, while he himself was having the boiler and wrought-iron work constructed in Cornwall. The engine had been ordered as a portable pumping engine, for removing water from the foundation of a bridge at Exeter; but before sending it to its destination, he had arranged to plough with it, as a means of perfecting the plans and drawings for a more suitable ploughing engine then in construction, to be fitted "with boiler, wheels, and everything complete for ploughing and thrashing, as shown in the drawing." The friction of the wheels on the ground would be greater than the power of the engine; therefore they would not slip when the full power was applied to draw a plough any more than the Welsh engine, the wheels of which did not slip though resting on smooth iron. One of his small engines, which had been at work in a mine, was sent as a thrashing engine to Padstow. It is evident that, having given a portion of his attention for a year or two to the question of steam agriculture, A drawing by Trevithick—having as usual neither name, date, nor scale, nor writing of any kind, but the watermark in the paper is 1813—illustrates his ideas expressed to Sir Charles Sinclair in 1812:—"It is my opinion that every part of agriculture might be performed by steam." The thrashing and grinding engines were at work, and the tormenting harrowing engine was probably designed for bringing under steam cultivation the extensive commons referred to. In those days, before the practice of underground drainage, the surface of cultivated land was thrown into furrows, or a series of small hills and vales, the latter acting as the surface drain for carrying off the water. Suppose the first step in cultivating a common to be the breaking of the soil, and throwing it into uniform lines of rise and fall that facilitated drainage without inconveniencing the tillage, what better machine could have been devised than Trevithick's? A combination of the modern tormentor and harrow loosened the ground to the required depth, which was then, by a revolving wheel with spades, thrown on one side, resulting in uniform lines of ridges and hollows. The steam-shoveller was removed, or the tormentor irons raised, when only the harrow was required. The absence of the ordinary shafts at the front end of the framing indicates that the spade-tormentor was not to be drawn by horses, but whether by a locomotive or by a fixed engine is not self-evident. Trevithick's Steam Spade-tormentor, 1813. [Rough draft.] "Mr. Kendal, "Sir,—I have yours of the 17th inst. The thrashing machine engine is ready for you, and shall be sent up immediately. I wish you to get about 100 fire bricks, 200 common bricks, 20 loads of stone, and 20 bushels of lime. The house will get finished while I am fixing the engine. About 1500 or 1600 weight of iron for your engine has been sent to the Blue Hills Mine, St. Agness. I wish you could send down your cart to fetch it from there to Padstow. There is no part of these castings but may be easily conveyed in a common butt or cart. When you have the stone, brick, and lime ready, and a cart to send to St. Agness for the castings, please to write me, and I will come to Padstow at the same time with them, and finish the engine. The sooner you get ready the better, as I expect to have an engagement in about four weeks' time, that would prevent my coming to Padstow for some time; therefore I wish to get your engine finished before that time. Please to write me as early as possible, and let me know when you will be ready for me, and what day I shall meet your cart at St. Agness for the castings. "Your obedient servant, Real inventors hesitate not to erect their own engines, lend a hand in building the house, walk to the scene of action, or take a lift in a cart; and by such steps was the gift of genius moulded to the wants of daily life; while the modern engineer of eminence, living in large cities, knows little of the minutiÆ of his work, or even of the working mechanics on whose skill the success of his ideas is dependent. "In 1815, Mr. Kendal, the proctor of Padstow, sent for me to repair his steam-engine. To prevent the old disputes in collecting his corn tithes, he had at work one of Captain Trevithick's steam thrashing machines. The small farmers "In 1818 I put a new four-way cock to a thrashing engine that Captain Trevithick had made for Mr. Kendal, of Padstow, who was the receiver of tithe corn. The boiler was a tube of wrought iron, about 4 feet in diameter and 6 feet long, standing on its end. The cylinder was fixed in the top of the boiler; an upright from the top of the cylinder supported the fly-wheel shaft; a connecting rod from the crank-pin in the fly-wheel was fastened to a joint-pin in the piston. The cylinder had no cover. The four-way cock was worked by an excentric on the shaft, moving a lever, which was kept in contact with the excentric by a spring." "About 1824 I worked in Binner Downs Mine one of Captain Trevithick's puffer whim-engines. The boiler was cylindrical, made of wrought iron. It stood on its end, with the fire under it, and brick flues around it. The cylinder was let down into the top of the boiler. A four-way cock near the top of the cylinder turned the steam on and off. The fly-wheel and its shaft were fixed just over the cylinder. A lever and rod worked the four-way cock and feed-pole. The waste steam puffed through a launder into the feed-cistern. The cylinder was about 12 inches in diameter, with a 3-feet stroke." Mr. Kendal's steam thrashing machine remained at work at least six years, during which time the only apparent repair was the four-way cock, worked by an excentric, which, if neglected, was apt to stick fast in its shell. One of the puffer-whims erected about this time was similar to the thrashing engine for Padstow, differing from the earlier one made for Sir C. Hawkins, in [Rough draft.] "Sir, "I have your favour of the 11th inst. respecting a steam-engine for thrashing. I have made several, all of which answer the purpose exceedingly well. They are made on a very simple construction so as to be free from repairs, and are kept in order and worked by the farm labourers, who never before saw a steam-engine. The first I made on this plan was for Sir Christopher Hawkins, who resides at this time in Argyll Street, Oxford Street, London. If you call on him, he, I doubt not, would give you every information you require respecting its performance. This was a fixed engine, because it was only required to work on one farm. It has been at work nearly eighteen months, and has not cost anything in repairs, nor any assistance but from the labourer who puts in the corn; he only gives three or four minutes every hour to put on a little coal. A few pails of water, put into the furnace in the morning, is sufficient for a day's work. They have at different times tried what duty the engine would perform with a given quantity of coal, and found that two Cornish bushels, weighing 168 lbs., would get up steam and thrash 1500 sheaves of wheat in about six hours. "Before this engine was erected, they usually thrashed 500 sheaves, with three heavy cart-horses for a day's work. I cannot say exactly the measurement of the corn that it thrashed, but it was considerably above 60 winchesters of wheat with 168 lbs. of coal; not a halfpenny in coal for each winchester of wheat. "The engines that I have since erected have performed the same duty. "The horse machinery is thrown out of use, but the same drum is turned by the engine. "A fixed engine of this power I would deliver to you in London for 100 guineas; it would cost you about 15l. more to fix the furnace in brickwork. "A portable engine costs 160 guineas, but it would cost nothing in erecting, as it will be sent with chimney and every "If you have not sufficient work for it you can lend it to your neighbours. The last engine I erected was about three weeks since, for a farmer that kept four horses and two drivers. The parts of the horse machine thrown out of use, together with the four horses, sold for more money than he gave me for the engine, exclusive of 4l. per week that it cost him in horse keep and drivers to thrash 3000 sheaves per week. "Now the engine performs more than double that work, and does not cost above 10s. per week; and the labourer in the barn does double the work he did before for the same money. If you wish the same engine to have sufficient power to turn one pair of mill-stones, the cost will be 220 guineas. "Mr. J. Rawlings, Strood, Kent." "Dear Trevithick, "Messrs. Hazeldine, Rastrick, and Co., "Gentlemen,—Lord Dedunstanville's engine thrashed yesterday 1500 sheaves in 90 minutes with 40 lbs. of coal. The first steam thrashing engine was worked by a labouring man for eighteen months, without needing repair, or even attention beyond three or four minutes each hour to put on a little coal. Necessary stoppages for various purposes caused a day's work to be no more than the engine could perform in half a day. No additional feed-water was required during an ordinary day's work to thrash 1500 sheaves of wheat with 168 lbs. of coal, while on a special occasion that quantity was thrashed in an hour and a half, consuming only 40 lbs. of coal. Three horses during three days were required to do the same amount of work. A farmer sold his horses used in thrashing Such an engine could be delivered in London for 100 guineas, while a portable engine on wheels with a differently constructed boiler, requiring no mason work, would cost 160 guineas. [Rough draft.] "Gentlemen, "I have your favour of the 9th August, respecting steam-engines for St. Kitts. I fear it will not be possible to get an engine ready by the 1st of November. "As you say the gentleman that is about to take them out is a clever man, and likely to promote the use of them, I will make immediate inquiry, and, if possible, will get one ready, of which I will inform you in a short time. "I very much wish that every person who intends to employ a steam-engine of mine would first examine the engine, and be satisfied with the construction before giving an order, for which reason I must request you to send your friend down to Messrs. Hazeldine and Rastrick's foundry, Bridgenorth, Shropshire, where he may see the portable steam-engine that was made for Mr. Pickwood, which the founders will set to work for his inspection in half an hour after his arrival. As this gentleman has a taste for machines, and wishes to make himself fully acquainted with the principle and use of the steam-engine, he will be much gratified with the sight of this curious machine and with the information he will receive from the founders, which will be essentially necessary to him before leaving England. "I am extremely disappointed that this engine was not forwarded to Mr. Pickwood, as I find from his letter that he has an exceedingly clever and active mind, and is a very fit person to take the management of introducing a machine into a new country. "This engine is engaged by a Spanish gentleman, who is "I remain, your obedient servant, "Messrs. Plummer, Barham, and Co., "N.B.—If your friend goes to Bridgenorth, let him show this letter to the founders." The engine, intended for the West Indies, so pleased Mr. Uville, that he begged to have it made over to him for South America, where it worked the machinery for rolling gold and silver in the Mint at Lima. "About 1815, while erecting a high-pressure pole-engine at Legassack for Mr. Trevithick, and doing some repairs to Mr. Kendal's thrashing engine, a Creole, I think called Nash, brought a note from Captain Trevithick, stating that the bearer was anxious to be taught to erect and work the portable engines for Jamaica. "Sir Rose Price, who had property in the West Indies, had sent him to Mr. Trevithick for that purpose." It is therefore probable that some of Trevithick's engines reached Jamaica. Sir Rose Price was well known to Lord Dedunstanville and Sir Charles Hawkins, and living near them, saw the engines at work and their fitness for his property in Jamaica. Lord Dedunstanville's engine of 1812 was sold as old iron to Messrs. Harvey and Co. not long before 1843. Having remained for some time on the old-scrap heap, it was in that year again worked to drive machinery. Instead of the original rope-driver on the fly-wheel, a chain was used, the links of which caught on projecting pins on the driving wheel. In that form it continued to work until 1853, before which it was fre What greater proof could be given of the fitness of design of this early engine, than its long life of forty years under such rough treatment, and the facility with which it was applied to different uses. Mr. Bickle, who, from recollection, had made a sketch of this engine before the writer had found Trevithick's sketch, says that after the engine had ceased to work, the boiler was turned to account in heating tar in the ship-builder's yard. "In 1854 I saw working in a shed at Carnsew, in the ship-building yard of Harvey and Co., of Hayle, an engine working a stamps for pounding up the slag and furnace bottoms from the brass-casting foundry. "I was then the foreman hammerman in Harvey and Co.'s smiths' shop and hammer-mill, and frequently noticed this old engine and inquired about it. It had been brought from Lord Dedunstanville's, at Tehidy Park, where it at one time worked a thrashing machine. The boiler was of wrought iron, built in brickwork, and looked like a big kitchen-boiler. A flattish cover was bolted on to the top of the boiler, and the cylinder was let down into this top. "The cylinder had no cover; it was about 8 or 10 inches in diameter and 2 or 3 feet stroke. The piston was a very deep one, with a joint for the connecting rod which went direct to the crank, which was supported on two upright stands from the cover on the boiler. The fly-wheel had a balance-weight for the down-stroke. A pitch-chain for driving passed over the wheel, which had pins in it, or projections, to catch into the square links of the driving chain; it was worked by a four-way cock." "About 1843, when we were building iron boats for the Rhine, the old engine was put to work to drive the tools or machinery in the yard. She was very useful to us and worked very well. She worked about ten years, and was then thrown "My father (then the foreman boiler-maker) about twenty-four years ago took the old engine from the scrap heap, where it had been for many years, and set it to work in the tool shop. My father said it had come from Tehidy as old iron." The use of the high-pressure steam agricultural engine was not confined to Cornwall. Mr. H. Pape, still carrying on business in Hazeldine and Rastrick's old engine manufactory at Bridgenorth, says:— "My father worked as a smith under Mr. Rastrick. Mr. Hazeldine had the foundry when Trevithick's engines were made, and have heard my father speak of them. I have seen three of them at work in Bridgenorth; one of them at Mr. Jasper's flour-mill, it drove four stones, and continued in work up to 1837; one at Sing's tan-yard worked up to 1840; and one was on Mr. Jasper's farm at Stapleford for doing farm work. Mr. Smith, now on the farm, worked it up to about 1858. "The engines that worked in Bridgenorth had cast-iron cylinders for the outer casing of the boiler, one cylinder for small engines, three or four cylinders bolted together for the larger ones. The fire-tube was wrought iron, the chimney stood up by the fire-door. The cylinder was let down into the boiler; it worked with a four-way cock. There was a piston-rod, cross-head, two guide-rods on the top of the cylinder, and two side rods to the crank and pin in 'the fly-wheel.'" "My first husband had to do with the foundry; his father, Mr. Hazeldine, was a partner with Mr. Davies and Co. in 1816. In 1817 the partnership was broken up, and the foundry carried on by Hazeldine. I used to have two or three drawers full of drawings and account-books that were brought from the The engines described by Mr. Pape are of the type made by Trevithick, in Wales, about 1804, having a fire-place in the boiler, and similar in form to the Welsh locomotive. The drawings which served to light the fires certainly included Trevithick's plans for the steam-locomotive, ploughing engine, the screw-propeller, and many others of equal interest. "Dear Sir, "My grandfather's name was John Jasper, Esq., of Stableford; he must have been one, if not the first, user of a steam-engine for thrashing, winnowing, and shaking the straw all at one operation; it may have been erected eighty years ago, for an old servant of the family just now dead, aged ninety, worked when a boy in the steam-mill at Bridgenorth erected by my grandfather about the same time. "The thrashing engine was a side-lever engine, worked with a three side-way cock and tappet, a cylinder about 8¼ inches in diameter, and a 3 feet 4 inch stroke, cast-iron crank-shaft, cross-head, and guides. The boiler was placed underneath the engine, the fire under it, with brick flues. The boiler was about 9 feet long and 4 feet diameter. "The old side rods made of wood are still here, and so was the engine until about twelve years ago. I sent the cylinder, &c., to Coalbrookdale. "I am, Sir, The Stableford agricultural engine was probably made in 1804. The cylinder, of 8¼ inches in diameter, is precisely the size of that in the Welsh locomotive, The engines specially referred to in this chapter fully prove, from their length of service, the practical character of Trevithick's inventions, and of his having persevered with his high-pressure portables until their usefulness as locomotives and as agricultural helps had been established; but the ploughing, though fully designed, and probably put into practice, was not followed up to the same approach to perfection, or the record of its progress has been lost. Since the foregoing was written, the following has been received:— "Dear Sir', "The engine you refer to is still occasionally used here; when first erected there was a large quantity of corn thrashed by it, but of late years it has not been much used except for chaffing, bruising, &c. "I remain, dear Sir, "F. Trevithick, Esq." Trevithick's Trewithen engine, which sixty years ago was more manageable than horses going momentarily faster or slower at the will of a common labourer, His preparations for South America, and application of high steam in the large Cornish pumping engines, interfered with the perfecting the smaller agricultural work. |
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