Various

[The following article, from the pen of Hon. R. J. Walker, forms the Appendix to the volume just published in England, and now exciting great attention there, containing the various pamphlets issued by him during the last six months. The subjects discussed embrace Jefferson Davis and Repudiation, Recognition, Slavery, Finances and Resources of the United States. It would be difficult to overestimate the effect of these Letters abroad. As our readers already possess them in the pages of The Continental, we enable them to complete the series by furnishing the ensuing Appendix. It closes with an extract from an 'Introductory Address' delivered by Mr. Walker before the National Institute, at Washington, D. C., giving a short account of the various improvements and discoveries made by our countrymen in the Inductive Sciences. As showing to England what a high rank we had even then taken in the world of science, and pointing out to her the number and fame of our savants, it will be read with just pride and interest. As the Address was delivered in 1844, it of course contains no details of our marvellous progress since that date in science and discovery.—Ed. Continental.]

We have seen by the Census Tables, if the product per capita of the Slave States in 1859 had been equal to that of the Free States for that year, that the ADDITIONAL value produced in 1859 in the Slave States would have been $1,531,631,000. Now as our population augmented during that decade 35.59 per cent., this increased value, at that ratio, in 1869 would have been $2,052,332,272. If multiplying the amount each year by three only, instead of 3-559/1000 the result, during that decade, would have been as follows:

That is, the total increased product of the Slave States, during the decade from 1859 to 1869, would have been $17,873,539,511, if the production in the Slave States had been equal, per capita, to that of the Free States. This, it will be remembered, is gross product. This, it will be perceived, is far below the actual result, as we can see by comparing the real product of 1869, $2,052,332,272, as before given, with the $2,034,317,524, as the result of a multiplication by three each year.

The ratio of the increase of our wealth, from 1850 to 1860, as shown by the census, was much greater than that of our population—namely, 126.45 per cent. Multiplying by this ratio (126.45), the result would be an additional product in 1860, in the Slave States, of $3,427,619,475. But our wealth increases in an augmented ratio during each decade.

Thus, the ratio of the increase of our wealth, as shown by the census, was as follows:

Thus, the increase of our wealth from 1840 to 1850, was more than 50 per cent. greater than from 1830 to 1840; and from 1850 to 1860, nearly double that from 1840 to 1850. At the same duplicate ratio, from 1850 to 1870, the result would be over 250 per cent. That such would have been a close approximation to the true result, is rendered still more probable by the fact, that the product of 1859, as shown by the census, was 250 per cent. greater than that of 1849.

If, then, instead of 126.45 per cent., we were to assume 250 per cent. as the ratio, the result would be in 1869, $5,297,708,612, as the increased product of the Slave States that year, if the ratio per capita were equal to that of the Free States. If we carry out these ratios from 1859 to 1869, either of 126.45, or of 250, into the aggregate of the decade, the results are startling. Assuming, however, that of the population only, we have seen that the aggregate result in the decade from 1859 to 1869 was over seventeen billions of dollars, or largely more than ten times our debt incurred by this rebellion.

When, then, I reassert the opinion, heretofore expressed by me, that as the result of the superiority of free over slave labor, our wealth in 1870, and especially in each succeeding decade, as a consequence of the entire abolition of Slavery in the United States, will be far greater, notwithstanding the debt, than if the rebellion had never occurred, there is here presented conclusive official proof of the truth of this statement. We have seen that our wealth increased from 1850 to 1860, 126.45 per cent., whilst that of England, from 1851 to 1861, augmented only at the rate of 37 per cent.

Applying these several ratios to the progress of the wealth of the United Kingdom and the United States, respectively, in 1870, 1880, 1890, and 1900, the result is given below.

We have seen by the census, that our national wealth was, in

Increase from 1850 to 1860, 126.45 per cent.

England, from 1851 to 1861, 37 per cent.

Assuming these ratios, the result would be as follows:

Thus, it appears by the census of each nation, that, each increasing in the same ratio respectively as for the last decade, the wealth of the United States in 1880 would exceed that of the United Kingdom $23,743,518,849; that in 1890 it would be much more than double, and in 1900, approaching quadruple that of the United Kingdom.

When we reflect that England increases in wealth much more rapidly than any other country of Europe, the value of these statistics may be estimated, as proving how readily our national debt can be extinguished without oppressive taxation.

These are the results, founded on the actual statistics, without estimating the enormous increase of our national wealth, arising from the abolition of Slavery. We have seen that, by the official tables of the census of 1860, the value of the products of the United States, so far as given, for the year 1859, was $5,290,000,000. But this is very short of the actual result. The official report (pages 59, 190, 198 to 210) shows that this included only the products of 'agriculture, manufactures, mines, and fisheries.' In referring to the result as to 'manufactures,' at page 59 of his official report before given, the Superintendent says: 'If to this amount were added the very large aggregate of mechanical productions below the annual value of $500, of which no official cognizance is taken, the result would be one of startling magnitude.'

1. This omission alone, for gross product, is estimated at $500,000,000.

2. Milk and eggs, fodder, wood, poultry, and feathers, omitted, gross products, estimated at $350,000,000.

3. Gross earnings of trade and commerce, including freights, &c., by land and water, $1,000,000,000.

4. Gross earnings of all other pursuits and business, including all other omissions, $1,000,000,000.

Total gross products of 1860, as thus estimated, $8,140,000,000, of which the amount for the Free States, as estimated, is $6,558,334,000, and for the Slave States, $1,581,666,000.

I have heretofore referred to the vast influence of education as one of the principal causes of the greater product per capita in the Free than in the Slave States, of the much larger number of patents, of inventions, and discoveries, in the former than in the latter.

At the April meeting of 1844, upon the request of the Society, I delivered at Washington (D. C.) the Introductory Address for the National Institute, in which, up to that date, an account was given by me of 'the various improvements and discoveries made by our countrymen in the inductive sciences.' On reference to that address, which was published at its date (April, 1844), with their bulletin, it will be seen that, from the great Franklin down to Kinnersley, Fitch, Rumsey, Fulton, Evans, Rush, the Stevenses of New Jersey, Whitney, Godfrey, Rittenhouse, Silliman, J. Q. Adams, Cleveland, Adrain, Bowditch, Hare, Bache, Henry, Pierce, Espy, Patterson, Nulty, Morse, Walker, Loomis, Rogers, Saxton, and many others; these men, with scarcely an exception, were from the Free States.

EXTRACT.

And, first, of electricity. This has been cultivated with the greatest success in our country, from the time when Franklin with his kite drew down electricity from the thunder cloud, to that when Henry showed the electrical currents produced by the distant lightning discharge. In Franklin's day the idea prevailed that there were two kinds of electricity, one produced by rubbing vitreous substances, the other by the friction of resinous bodies. Franklin's theory of one electric fluid in all bodies, disturbed in its equilibrium by friction, and thus accumulating in one and deserting the other, maintains its ground, still capable of explaining the facts elicited in the progress of modern discovery. Franklin believed that electricity and lightning were the same, and proceeded to the proof. He made the perilous experiment, by exploring the air with a kite, and drawing down from the thunder cloud the lightning's discharge upon his own person. The bold philosopher received unharmed the shock of the electric fluid, more fortunate than others who have fallen victims to less daring experiments. The world was delighted with the discoveries of the great American, and for a time electricity was called Franklinism on the continent of Europe; but Franklin was born here, and the name was not adopted in England. While Franklin made experiments, Kinnersley exhibited and illustrated them, and also rediscovered the seemingly opposite electricities of glass and resin. Franklin's lightning rod is gradually surmounting the many difficulties with which it contended, as experience attests the greater safety of houses protected by the rod, properly mounted, whilst the British attempt to substitute balls for points has failed. This question, as to powder magazines, has lately excited much controversy. Should a rod be attached to the magazine, or should it be placed upon a post at some distance? This question has been solved by Henry. When an electrical discharge passes from one body to another, the electricity in all the bodies in the neighborhood is affected. Henry magnetized a needle in a long conductor, by the discharge from a cloud, more than a mile from the conductor. If a discharge passes down a rod, attached to a powder house, may it not cause a spark to pass from one receptacle for powder to another, and thus inflame the whole? The electrical plenum, which Henry supposed, is no doubt disturbed, and to great distances; but the effect diminishes with the distance. If all the principal conductors about a building can be connected with a lightning rod, there is no danger of a discharge; for it is only in leaving or entering a conductor that electricity produces heating effects; but if not, the rod is safer at a moderate distance from the building. The rate at which electricity moved was another of the experiments of Franklin. A wire was led over a great extent of ground, and a discharge passed through it. No interval could be perceived between the time of the spark passing to and from the wire at the two ends. Not long since, Wheatston of England, aided by our own great mechanic, Saxton, solved the problem. This has induced Arago, of France, to propose to test the rival theories of light, by similar means—to measure thus a velocity, to detect which has heretofore required a motion over the line of the diameter of the earth's orbit.

In galvanism, our countrymen have made many important discoveries. Dr. Hare invented instruments of such great power as well to deserve the names of calorimeter and deflagrator. The most refractory substances yielded to the action of the deflagrator, melting like wax before a common fire. Even charcoal was supposed to be fused in the experiments of Hare and Silliman, and the visionary speculated on the possibility of black as well as white diamonds. Draper, by his most ingenious galvanic battery, of two metals and two liquids, with one set of elements, in a glass tube not the size of the little finger, was able to decompose water. Faraday, of England, discovered the principle, that when a current of electricity is set in motion, or stopped in a conductor, a neighboring conductor has a current produced in the opposite direction. Henry proved that this principle might be made available to produce an action of a current upon itself, by forming a conductor in the whirls of a spiral, so that sparks and shocks might be obtained by the use of such spirals, when connected with a pair of galvanic plates, a current from which could give no sparks and no shocks. Henry's discoveries of the effects of a current in producing several alternations in currents in neighboring conductors—the change of the quality of electricity which gives shocks to the muscles into that producing heat, and vice versa—his mode of graduating these shocks—his theoretical investigations into the causes of these alternations—are abstruse, but admirable; and his papers have been republished throughout Europe. The heating effects of a galvanic current have been applied by Dr. Hare to blasting. The accidents which so often happen in quarries may be avoided by firing the charge from a distance, as the current which heats the wire, passing through the charge, may be conveyed, without perceptible diminution, through long distances. A feeble attempt to attribute this important invention of Dr. Hare to Colonel Pasley, an English engineer, has been abandoned. This is the marvellous agent by which our eminent countryman, Morse, encouraged by an appropriation made by Congress, will, by means of his electric telegraph, soon communicate information forty miles, from Washington to Baltimore, more rapidly than by whispering in the ear of a friend sitting near us. A telegraph on a new plan at that time, invented by Mr. Grout, of Massachusetts, in 1799, asked a question and received an answer in less than ten minutes through a distance of ninety miles. The telegraph of Mr. Morse will prove, I think, superior to all others; and the day is not distant when, by its aid, we may perhaps ask questions and receive replies across our continent, from ocean to ocean, thus uniting with steam in enlarging the limits over which our Republic may be safely extended.[2]

Many of our countrymen have contributed to the branch which regards the action of electrified and magnetic bodies. Lukens's application of magnetism to steel (called touching), the compass of Bissel for detecting local attraction, of Burt for determining the variation of the compass, and the observations on the variations of the needle made by Winthrop and Dewitt, deserve notice and commendation. Not long since, Gauss, of Germany, invented instruments by which the changes of magnetic variation and force could be accurately determined. Magnetic action is ever varying. The needle does not point in the same direction for even a few minutes together. The force of magnetism, also, perpetually varies. 'True as the needle to the pole' is not a correct simile for the same place, and, if we pass from one spot to another, is falsified at each change of our position; for the needle changes its direction, and the force varies. Enlarged and united observations, embracing the various portions of the world, must produce important results. The observations at Philadelphia, conducted by Dr. A. D. Bache, and now continued by him under the direction of the Topographical Bureau, are of great value, and will, it is hoped, be published by Congress. Part of them have already first seen the light in Europe—a result much to be regretted, for we are not strong enough in science to spare from the national records the contributions of our countrymen.

These combined observations, progressing throughout the world, are of the highest importance. The University of Cambridge, the American Philosophical Society, and Girard College have erected observatories; and one connected with the Depot of Charts and Instruments has been built in this city last year by the Government, and thoroughly furnished with instruments for complete observations. The names of Bache, Gillis, Pierce, Lovering, and Bond are well known in connection with these establishments.

A magnetic survey of Pennsylvania has been made by private enterprise, and the beginning of a survey in New York. Loomis has observed in Ohio, Locke in Ohio and Iowa, and to him belongs the discovery of the position of the point of greatest magnetic intensity in the Western World. Most interesting magnetic observations (now in progress of publication by Congress) are the result of the toilsome, perilous, and successful expedition, under Commander Wilkes, of our navy, by whom was discovered the Antarctic continent, and a portion of its soil and rock brought home to our country.

The analogy of the auroral displays with those of electricity in motion, was first pointed out by Dr. A. D. Bache, whose researches, in conjunction with Lloyd of Dublin, to determine whether differences of longitude could be measured by the observations of small simultaneous changes in the position of the magnetic needle, led to the knowledge of the curious fact, that these changes, which had been traced as simultaneous, or nearly so, in the continent of Europe, did not so extend across the Atlantic.

Kindred to these two branches are electro-magnetism and magneto-electricity, connected with which, as discoverers, are our countrymen Dana, Green, Hare, Henry, Page, Rogers, and Saxton. The reciprocal machine for producing shocks, invented by Page, and the powerful galvanic magnet of Henry, are entitled to respectful notice. This force, it was thought, might be substituted for steam; but no experiments have as yet established its use, on any important scale, as a motive power. The fact that an electrical spark could be produced by a peculiar arrangement of a coil of wire, connected with a magnet, is a recent discovery; and the first magneto-electric machine capable of keeping up a continuous current was invented by Saxton.

Electricity and magnetism touch in some points upon heat. Heat produces electrical currents; electrical currents produce heat. Heat destroys magnetism. Melted iron is incapable of magnetic influence. Reduction of temperature in iron so far decreases the force, that a celebrated philosopher made an elaborate series of experiments to ascertain whether a great reduction of temperature might not develop magnetic properties in metals other than iron. This branch of thermo-electricity has received from us but little attention. Franklin's experiments, by placing differently colored cloths in the snow, and showing the depth to which they sank, are still quoted, and great praise has been bestowed abroad on a more elaborate series of experiments, by a descendant of his, Dr. A. D. Bache, proving that this law does not hold good as to heat, unaccompanied by light. The experiments of Saxon and Goddard demonstrate that solid bodies do slowly evaporate. It is proper here to mention our countryman, Count Rumford, whose discoveries as to the nature and properties of heat, improvement in stoves and gunnery, and in the structure of chimneys and economy of fuel, have been so great and useful.

Light accompanies heat of a certain temperature. That it acts directly to increase or decrease magnetic force, is not yet proved; and the interesting experiments made by Dr. Draper, in Virginia, go to show that it is without magnetic influence. The discussion of this subject forms, the branch of optics, touching physical science on the one side, the most refined, and the highest range of mathematics on the other. Rittenhouse first suggested the true explanation of the experiment, of the apparent conversion of a cameo into an intaglio, when viewed through a compound microscope, and anticipated many years Brewster's theory. Hopkinson wrote well on the experiment made by looking at a street lamp through a slight texture of silk. Joscelyn, of New York, investigated the causes of the irradiation manifested by luminous bodies, as for instance the stars. Of late, photographic experiments have occupied much attention, and Draper has advanced the bold idea, supported by experiment, that the agent in the so-called photography, is not light, nor heat, but an agent differing from any other known principle. Henry has investigated the luminous emanation from lime, calcined with sulphur, and certain other substances, and finds that it differs much from light in some of its qualities.

Astronomy is the most ancient and highest branch of physics. One of our earliest and greatest efforts in this branch was the invention of the mariner's quadrant, by Godfrey, a glazier of Philadelphia. The transit of Venus, in the last century, called forth the researches of Rittenhouse, Owen, Biddle, and President Smith, near Philadelphia, and of Winthrop, at Boston. Two orreries were made by Rittenhouse, as also a machine for predicting eclipses. Most useful observations, connected with the solar eclipses, from 1832 to 1840, have been made by Paine, of Boston. We have now well-supplied observatories at West Point, Washington, Cambridge, Philadelphia, Hudson, Ohio, and Tuskaloosa, Alabama; and the valuable labors of Loomis, Bartlett, Gillis, Bond, Pierce, Walker, and Kendall are well known. Mr. Adams, so distinguished in this branch and that of weights and measures, laid last year the corner stone of an observatory at Cincinnati, where will soon be one of the largest and most powerful telescopes in the world. Most interesting observations as to the great comet of 1843 were made by Alexander, Anderson, Bartlett, Kendall, Pierce, Walker, Downes, and Loomis, and valuable astronomical instruments have been constructed by Amasa Holcomb, of Massachusetts, and Wm. J. Young, of Philadelphia.

It is difficult to class the brilliant meteors of November the 13th, 1833. If such meteors are periodic, the discovery was made by Professor Olmsted; and Mr. Herrick, of New Haven, has added valuable suggestions. The idea that observers, differently placed at the time of appearance and disappearance of the same meteor, would give the means of determining differences of longitude, was first applied in our own country, where the difference of longitude of Princeton and Philadelphia was determined by observations of Henry and Alexander, Espy and Bache. In meteorology our countrymen have succeeded well. Dr. Wells, of South Carolina, elaborated his beautiful and original theory of the formation of dew, and supported it by many well-devised and conclusive experiments. The series of hourly observations, by Professor Snell and Captain Mordecai, are well known; and the efforts of New York and Pennsylvania, of the medical department of the army, and its present enlightened head, Dr. Lawson, have much advanced this branch of science. The interesting question, Does our climate change? seems to be answered thus far in the negative, by registers kept in Massachusetts and New York. There are two rival theories of storms. That of Redfield, of a rotary motion of a wide column of air, combined with a progressive motion in a curved line. Espy builds on the law of physics, examines the action of an upmoving column of air, shows the causes of its motion and the results, and then deduces his most beautiful theory of rain and of land and water spouts. This he puts to the test of observation; and in the inward motion of wind toward the centre of storms, finds a striking verification of his theory. This theory is also sustained by the overthrow or injury, in the recent tornado at Natchez, of the houses whose doors and windows were closed, while those which were open mostly escaped unhurt. Mr. Espy must be considered, not only here, but throughout the world, as at the head of this branch of science. This subject has been greatly advanced by Professor Loomis, whose paper has been pronounced, by the highest authority, to be the best specimen of inductive reasoning which meteorology has produced. The most recent and highly valuable meteorological works of Dr. Samuel Forry are much esteemed. Many important discoveries in pneumatics were made by Dr. Franklin and Count Rumford, and the air pump was also greatly improved by Dr. Prince, of Salem.

Chemistry, in all its departments, has been successfully pursued among us. Dana, Draper, Ellet, Emmet, Hare, the Mitchells, Silliman, and Torrey, are well known as chemical philosophers; and Booth, BoyÉ, Chilton, Keating, Mather, R. Rogers, Seybert, Shepherd, and Vanuxen, as analysts; and F. Bache, Webster, Greene, Mitchell, Silliman, and Hare, as authors. In my native town of Northumberland, Pennsylvania, resided two adopted citizens, most eminent as chemists and philosophers, Priestley and Cooper. The latter, who was one of my own preceptors, was greatly distinguished as a writer, scholar, jurist, and physician, as well as a chemist. Priestley, although I do not concur in his peculiar views of theology, was certainly one of the most able and learned of ecclesiastical writers, and possessed also a mind most vigorous and original. His discoveries in pneumatic chemistry have exceeded those of any other philosopher. He discovered vital air, many new acids, chemical substances, paints, and dyes. He separated nitrous and oxygenous airs, and first exhibited acids and alkalies in a gaseous form. He ascertained that air could be purified by the process of vegetation, and that light evolved pure air from vegetables. He detected the powerful action of oxygenous air upon the blood, and first pointed out the true theory of respiration. The eudiometer, a most curious instrument for fixing the purity of air, by measuring the proportion of oxygen, was discovered by Dr. Priestley. He lived and died in my native town, universally beloved as a man, and greatly admired as a philosopher. Chemistry has actively advanced among us during the present century. Hare's compound blowpipe came from his hand so perfect, in 1802, that all succeeding attempts of Dr. Clark, of England, and of all others, in Europe and America, to improve upon it or go beyond the effects produced, have wholly failed. His mode of mixing oxygen and hydrogen gases, the instant before burning them, was at once simple, effective, and safe. The most refractory metallic and mineral substances yielded to the intense heat produced by the flame of the blowpipe. In chemical analysis, the useful labors of Keating, Vanuxen, Seybert, Booth, Clemson, Litton, and Moss, would fill many volumes. In organic chemistry, the researches of Clark, Hare, and BoyÉ were rewarded by the discovery of a new ether, the most explosive compound known to man. Mitchell's experiments on the penetration of membranes by gases, and the ingenious extension of them by Dr. Rogers, are worthy of all praise. The softening of indiarubber, by Dr. Mitchell, renders it a most useful article. Dyer's discovery of soda ash yielded him a competence. Our countrymen have also made most valuable improvements in refining sugar, in the manufacture of lard oil and stearin candles, and the preservation of timber by Earle's process. Sugar and molasses have been extracted in our country from the cornstalk, but with what, if any profit, as to either, is not yet determined. No part of mechanics has produced such surprising results as the steam engine, and our countrymen have been among the foremost and most distinguished in this great and progressive branch. When Rumsey, of Pennsylvania, made a steamboat, which moved against the current of the James River four miles an hour, his achievement was so much in advance of the age, as to acquire no public confidence. When John Fitch's boat stemmed the current of the Delaware, contending successfully with sail boats, it was called, in derision, the scheme boat. So the New Yorkers, when the steamboat of their own truly great mechanic, Stevens, after making a trip from Hoboken, burnt accidentally one of its boiler tubes, it was proclaimed a failure. Fulton also encountered unbounded ridicule and opposition, as he advanced to confer the greatest benefits on mankind by the application of steam to navigation. So Oliver Evans, of Pennsylvania (who has made such useful improvements in the flour mill), was pronounced insane, when he applied to the Legislatures of Pennsylvania and Maryland for special privileges in regard to the application of steam to locomotion on common roads. In 1810 he was escorted by a mob of boys, when his amphibolas was moved on wheels by steam more than a mile through the streets of Philadelphia to the river Schuylkill, and there, taking to the water, was paddled by steam to the wharves of the Delaware, where it was to work as a dredging machine. Fulton's was the first successful steamboat, Stevens's the first that navigated the ocean, Oliver Evans's the first high-pressure engine applied to steam navigation. Stevens's boat, by an accident, did not precede Fulton's, and Stevens's engine was wholly American, and constructed entirely by himself, and his propeller resembled much that now introduced by Ericsson. Stevens united the highest mechanical skill with a bold, original, inventive genius. His sons (especially Mr. Robert L. Stevens, of New York) have inherited much of the extraordinary skill and talent of their distinguished father. The first steamboat that ever crossed the ocean was built by one of our countrymen, and their skill in naval architecture has been put in requisition by the Emperor of Russia and the Sultan of Turkey. The steam machines invented by our countrymen to drive piles, load vessels, and excavate roads, are most ingenious and useful. The use of steam, as a locomotive power, upon the water and the land, is admirably adapted to our mighty rivers and extended territory. From Washington to the mouth of the Oregon is but one half,[3] and to the mouth of the Del Norte but one fourth, of the distance of the railroads already constructed here; and to the latter point, at the rate of motion (thirty miles an hour) now in daily use abroad, the trip would be performed in two days, and to the former in four days. Thus, steam, if we measure distance by the time in which it is traversed, renders our whole Union, with its most extended limits, smaller than was the State of New York ten years since. Steam cars have been moved, as an experiment, both here and abroad, many hundred miles, at the rate of sixty miles an hour; but what will be the highest velocity ultimately attained in common use, either upon the water or the land, is a most important problem, as yet entirely unsolved. Our respected citizens, Morey and Drake, have endeavored to substitute the force of explosion of gaseous compounds for steam. The first was the pioneer, and the second has shown that the problem is still worth pursuing to solution. An energetic Western mechanic made a bold but unsuccessful effort to put in operation an engine acting by the expansion of air by heat; and a similar most ingenious attempt was made by Mr. Walter Byrnes, of Concordia, Louisiana; as also to substitute compressed air, and air compressed and expanded, as a locomotive power. All attempts to use air as a motive power, except the balloon, the sail vessel, the air gun, and the windmill, have thus far failed; but what inventive genius may yet accomplish in this respect, remains yet undetermined. There is, it is true, a mile or more of pneumatic railway used between Dublin and Kingstown. An air pump, driven by steam, exhausts the air from a cylinder in which a piston moves; this cylinder is laid the whole length of the road, and the piston is connected to a car above, so that, as the piston moves forward on the exhaustion of the air in front of it, the car is also carried forward. The original idea of this pneumatic railway was derived from the contrivance of an American, quite unknown to fame, who, as his sign expressed it, showed to visitors a new mode of carrying the mail,[4] more simple, and quite as valuable, practically, as this atmospheric railway. The submerged propeller of Ericsson, and the submerged paddle wheel, the rival experiments of our two distinguished naval officers, Stockton and Hunter, are now candidates for public favor; and the Princeton on the ocean, as she moves in noiseless majesty, at a speed never before attained at sea, seems to attest the value of one of these experiments, while the other is yet to be determined. The impenetrable iron steam vessel of Mr. Stevens is not yet completed, nor have those terrific engines of war, his explosive shells, yet been brought to the test of actual conflict.

In curious and useful mechanical inventions, our countrymen are unsurpassed, and a visit to our new and beautiful Patent Office will convince the close observer that the inventive genius of America never was more active than at the present moment. The machines for working up cotton, hemp, and wool, from their most crude state to the finest and most useful fabrics, have all been improved among us. The cotton gin of Eli Whitney has altered the destinies of one third of our country, and doubled the exports of the Union. The ingenious improvements for imitating medals, by parallel lines upon a plain surface, which, by the distances between them, give all the effects of light and shade that belong to a raised or depressed surface, invented by Gobrecht and perfected by Spencer, has been rendered entirely automatic by Saxton, so that it not only rules its lines at proper distances and of suitable lengths, but when its work is done it stops. In hydraulics, we have succeeded well; and the great aqueduct over the Potomac at Georgetown, constructed by Major Turnbull, of the Topographical Corps, exhibits new contrivances, in overcoming obstacles never heretofore encountered in similar projects, and has been pronounced in Europe one of the most skilful works of the age.

The abstract mathematics does not seem so well suited to the genius of our countrymen as its application to other sciences. Those among us who have most successfully pursued the pure mathematics, are chiefly our much-esteemed adopted citizens, such as Nulty, Adrain, Bonnycastle, Gill, and Hassler. Bowditch was an American, and is highly distinguished at home and abroad. Such men as Plana and Babbage rank him among the first class, and his commentary on the 'MÉcanique CÉleste' of Laplace, has secured for him a niche in the temple of fame, near to that of its illustrious author. Anderson and Strong are known to all who love mathematics, and Fischer was cut off by death in the commencement of a bright career. And may I here be indulged in grateful remembrance of two of my own preceptors, Dr. R. M. Patterson and Eugene Nulty. The first was the professor at my Alma Mater (the University of Pennsylvania) in natural philosophy and the application of mathematics to many branches of science. He was beloved and respected by all the class, as the courteous gentleman and the profound scholar; and the Mint of the United States, now under his direction, at Philadelphia, has reached the highest point of system, skill, and efficiency. In the pure mathematics Nulty is unsurpassed at home or abroad. In an earlier day, the elder Patterson, Ellicot, and Mansfield cultivated this branch successfully in connection with astronomy.

A new and extensive country is the great field for descriptive natural history. The beasts, birds, fishes, reptiles, insects, shells, plants, stones, and rocks are to be examined individually and classed; many new varieties and species are found, and even new genera may occur. The learned Mitchell, of New York, delighted in these branches. The eminent Harlan, of Philadelphia, and McMultrie were of a later and more philosophic school. Nuttall, of Cambridge, has distinguished himself in natural history, and Haldeman is rising to eminence.

Ornithology is one of the most attractive branches of natural history. Wilson was the pioneer; Ord, his biographer, followed, and his friend Titian Peale; Audubon is universally known, and stands preËminent; and the learned Nuttall and excellent and enthusiastic Townsend are much respected. Most of these men have compassed sea and land, and encountered many perils and hardships to find their specimens. They have explored the mountains of the North, the swamps of Florida, the prairies of the West, and accompanied the Exploring Expedition to the Antarctic, and round the world. As botanists, the Bartrams, Barton, and Collins, of Philadelphia, Torrey, of New York, Gray and Nuttall of Cambridge, Darlington, of Westchester, are much esteemed. The first botanical garden in our country was that of the Bartons, near Philadelphia; and the first work on botany was from Barton, of the same city. Logan, Woodward, Brailsford, Shelby, Cooper, Horsfield, Colden, Clayton, Muhlenburg, Marshall, Cutler, and Hosack, were also distinguished in this delightful branch.

A study of the shells of our country has raised to eminence the names of Barnes, Conrad, Lea, and Raffinesque. The magnificent fresh-water shells of our Western rivers are unrivalled in the Old World in size and beauty. How interesting would be a collection of all the specimens which the organic kingdom of America presents, properly classified and arranged according to the regions and States whence they were brought! Paris has the museum of the natural history of France, and London of Great Britain; but Washington has no museum[5] of the United States, though so much richer in all these specimens.

In mineralogy, the work of Cleveland is most distinguished. Shepherd, Mather, Troost, Torrey, and a few others, still pursue mineralogy for its own sake; but, generally, our mineralogists have turned geologists, studying rocks on a large scale, instead of their individual constituents, and vieing with their brethren in Europe in bold and successful generalization, and in the application of physical science to their subject. Maclure was one of the pioneers, and Eaton and Silliman contributed much to the stock of knowledge. This school has given rise to the great geological surveys made or progressing in several of the States. Jackson, in Maine, Hitchcock, in Massachusetts; Vanuxen, Conrad, and Mather, in New York; the Rogerses, in New Jersey, Pennsylvania, and Virginia; Ducatel, in Maryland; Owen and Locke, in the West; Troost, in Tennessee; Horton, in Ohio; the courageous, scientific, and lamented Nicolet, in Missouri, Iowa, and Wisconsin, have made contributions, not only to the geology of our country, but to the science of geology itself, which are conceded to be among the most valuable of the present day. The able reports of Owen and Nicolet were made to Congress, and deserve the highest commendation.

In geographical science, the explorations of Lewis and Clark; of Long, Nicolet, and the able and intrepid Fremont; the effective State survey of Massachusetts; the surveys of our public lands; the determination of the boundaries of our States, and especially those of Pennsylvania, by Rittenhouse and Elliott; of part of Louisiana, by Graham and Kearny; of Michigan, by Talcott; and of Maine, by Graham; have gained us great credit. The national work of the coast survey, begun by the late Mr. Hassler, and prosecuted through all discouragements and difficulties by that indomitable man, has reflected honor upon his adopted country, through the Government which liberally supported the work, and through whose aid it is now progressing, under new auspices, with great energy.[6] The lake survey is also now advancing under the direction of Captain Williams, of the Topographical Corps. Among the important recent explorations, is that of the enlightened, untiring, and intrepid Fremont, to Oregon, which fixes the pass of the Rocky Mountains within twenty miles of the northern boundary of Texas. Lieutenant Fremont is a member of the Topographical Corps, which, together with that of Engineers, contains so many distinguished officers, whose labors, together with those of their most able and distinguished chiefs, Colonel Totten and Colonel Abert, fill so large a portion of the public documents, and are so well known and highly appreciated by both Houses of Congress and by the country. The Emperor of Russia has entered the ranks of our Topographical Corps, and employed one of their distinguished members, Captain Whistler, to construct his great railroad from St. Petersburg to Moscow. The travels of our countrymen, Stephens, to Yucatan and Guatemala, to Egypt, Arabia, and Jerusalem, and of Dr. Grant to Nestoria, have increased our knowledge of geography and of antiquities, and have added new and striking proofs of the truths of Christianity.

Fossil geology occupied much of the time and attention of the great philosopher and statesman, Jefferson, and he was rewarded by the discovery of the megatherium. The mastodon, exhumed in 1801, from the marl pits of New York, by Charles Wilson Peale, has proved but one of an order of animal giants. Even the tetracaulodon, or tusked mastodon, of Godman, upon which rested his claims to fame, is not the most curious of this order, as the investigations of Hayes and Horner have proved. This order has excited the attention, not only of such minds as Cooper, Harlan, and Hayes, but has also occupied the best naturalists of France, Britain, Germany, and Italy.

Fossil conchology has attracted the attention of Conrad, the Lees, and the Rogerses, not only calling forth much ingenuity in description and classification, but also throwing great light upon the relative ages of some of the most interesting geological formations. The earthquake theory of the Rogerses is one of the boldest generalizations, founded upon physical reasoning, which our geologists have produced. In the parallel ridges into which the Apalachian chain is thrown, they see the crests of great earthquake waves, propagated from long lines of focal earthquake action, more violent than any which the world now witnesses. The geologist deals in such sublime conceptions as a world of molten matter, tossed into waves by violent efforts of escaping vapors, cooling, cracking, and rending, in dire convulsion. He then ceases to discuss the changes and formation of worlds, and condescends to inform us how to fertilize our soil, where to look for coal and iron, copper, tin, cobalt, lead, and where we need not look for either. He is the Milton of poetry, and the Watt of philosophy. And here let me add, that the recent application of chemistry to agriculture is producing the most surprising results, in increasing and improving the products of the earth, and setting at defiance Malthus's theory of population.

In medicine, that great and most useful branch of physics, our countrymen have been most distinguished. From the days of the great philosopher, physician, patriot, and statesman, Benjamin Rush, down to the present period, our country has been unsurpassed in this branch; but I have not time even to give an outline of the eminent Americans, whose improvements and discoveries in medicine have contributed so much to elevate the character of our country, and advance the comfort and happiness of man. Rush, one of the founders of this branch in America, was one of the signers of our Declaration of Independence, and his school of medicine was as independent and national as his course in our Revolutionary struggle. Statistics are chiefly concerned, as furnishing the facts connected with government and political economy, but they are also ancillary to physics. The statistical work of Mr. Archibald Russell, of New York, which immediately preceded the last census, contained many valuable suggestions, some of which were adopted by Congress; and had more been incorporated into the law, the census would have been much more complete and satisfactory. The recent statistical work of Mr. George Tucker, of Virginia, on the census of 1840, is distinguished by great talent and research, and is invaluable to the scholar, the philosopher, the statesman, and philanthropist.

[2] This address was made and published several months before any electric telegraph line was in operation, and is believed to be the first prediction of the success of this principle, as Continental or Oceanic.