Bathing is of several kinds. There is the morning tub and the sea dip which are taken to brace up the system; then there is the hot bath, more for sanitary and cleansing purposes; and finally come hot-air and vapour baths which are generally of a more or less medicinal character. These will be considered in rotation.

Cold Bathing.—All persons in health and of average strength may use a cold bath daily, in summer at least. In winter, mornings of extreme frost try the strongest constitution, and few are likely to benefit by a plunge on these occasions. For the most part, individuals of moderate powers and free from disease may carry the cleanly practice of summer through the winter months. A word on the bath itself. Those who take it should begin in summer, not winter, and so become gradually accustomed to its lowest temperature. No one should linger over it; 3-4 minutes are ample. After immersion, the body should be quickly and well dried and rubbed before dressing. Light gymnastic, dumb-bell, or club exercise, may occupy the next few minutes, the clothes being partly on if the weather be cold, and breakfast, or a cup of warm tea or coffee, should shortly follow, to prevent chilling.

There are those whom a cold bath injures, instead of invigorating. The readiest test of benefit is the glow of free surface-circulation, or at least the absence of any decided sense of chill after immersion. Some do not experience this. Among these are the subjects of heart weakness, arising from whatever cause; it may be consequent on organic disease of the heart, on old gout or rheumatism, or on overwork and underfeeding, in which case it is a part of a general debility. Again, there is in some a tendency to engorgement of one or other deep-seated organ with blood, a kidney, the liver, &c. This is commonly the result of a previous inflammatory attack, or of visceral disease at the time existing. Surface-cold aggravates the congestive tendency. Obviously, therefore, such persons, if they bathe, ought to use tepid water; and, in renal disorders, this method is often advantageous. In slight cases, cold is not injurious if the ablutions be expeditiously gone through, and restricted to periods of summer weather. The aged should avoid cold baths, and commonly do. Infants, if ordinary despatch is used in bathing and in dressing, have no reason to fear them. Their powers of reaction are excellent.

Cold baths chill down the feeble circulation of the badly nourished, and provoke a physical torpor which is obstructive to the processes of nutrition. They drive the blood from the surface of the body in upon vascular organs, whose circulation is already sluggish from general weakness. They thus produce discomforts which aggravate existing languor, and enhance the feeling that food and drink ought not to and therefore cannot be taken. A bath described as one “from which the chill has been taken” is too cold for subjects under medical advice who are in need of extra feeding.

In any case it is unwise to bathe out of doors when copious perspiration has continued for some hour or more, unless the weather be excessive or the sweating has been induced by loading with clothes rather than by exertion. When much perspiration has been produced by muscular exercise, it is unsafe to bathe, because the body is so fatigued or exhausted that the reaction—that is, the return of the momentarily displaced blood to the surface—cannot be ensured, and the effect may be to congest the internal organs and notably the nerve centres. From congestion of the nervous centres comes cramp, so often fatal in bathing.

If the weather be “chilly,” or there be a cold wind so that the body may be rapidly cooled at the surface while undressing, it is not safe to bathe. Under such conditions the further chill of immersion in cold water will take place at the precise moment when the reaction consequent upon the chill of exposure by undressing ought to occur, and this second chill will not only delay or altogether prevent the reaction, but convert the bath from a mere stimulant to a depressant, ending in the abstraction of a large amount of animal heat and congestion of the internal organs and nerve centres. The actual temperature of the water does not affect the question so much as its relative temperature as compared with that of the surrounding air. Practically, there ought to be a good deal of difference between the two, the water being much lower than the air and the body being—without great or long persisting perspiration—much warmer than the water, of course, but not so much warmer than the atmosphere as to be chilled by undressing. In short, the aim must be to avoid two chills; first, from the air, and second, from the water, and to make sure that the body is in such a condition as to secure a quick reaction on emerging from the water, without relying too much on the possible effect of friction by rubbing. It will be obvious that both weather and wind must be carefully considered before bathing is commenced, and that the state of the organism as regards fatigue and the force of the circulation should also be considered, not merely as regards the general habit, but the special condition when a bath is to be taken. These precautions are eminently needful in the case of the young or weakly.

Sea bathing is regarded, naturally, as more bracing in its character than river bathing. The saltness of the water and the sharp air of the sea together tend to invigorate us. As a rule, the bather can remain longer, without injurious effect, in salt than in fresh water. The sudden shock which results from a plunge into river or sea may be attended by bad effects in the case of persons who are subject to fits of any kind or to disturbance of the heart’s action. Another highly important question in bathing has reference to the care of the ears. Wherever any tendency to ear-ache or inflammation of the ear exists, bathing must be cautiously indulged in. A dive has been known to be followed by rupture of the “drum” of the ear, owing to the sudden pressure to which this membrane has been subjected in passing from the air under the water. Again, persons who have suffered from discharges from the ears—common after scarlet fever, for example—and in whom the drum of the ear may be perforated or irritable, abscess of the brain may follow injury produced by the sudden dive or by plunging the head beneath the water. Placing cotton wool in the ears is a necessary precaution for any who have tender ears, and a safe practice for all. Further, do not dive too much and avoid swimming on the back, for from the position of the ears the water gets into them a great deal more than even in diving. When getting out, besides giving a good rub down with a rough towel, always carefully wipe the ear and the glands behind the ear dry.

No child under 2 years of age ought, under any circumstances, to be bathed in the open sea, and no one, child or adult, can enter the sea without danger while under the influence of emotional excitement. Under 2 years of age, a child’s body is too weak to gain any benefit from the shock of immersion in the open sea. Its nervous and circulating forces are too feeble for the development of that vigorous reaction, without which sea-bathing is either useless or hurtful. In the absence of strength for such reaction a sea-bath tends to chill an infant’s body, and predispose to internal congestion. At any age the shock of immersion in the sea brings risk of danger, and even of death, when the emotions are powerfully excited, and especially when the mind and body are dominated by that most depressing of human emotions—fear. Infants are not always bathed in the sea merely with the intention of making them strong. There is an old seaside tradition that babies diligently bathed become fearless in the water when they grow up. This notion is also false. Than that infants gain courage by being plunged in the sea, it is more probable that many a nervous child has acquired a dread of bathing which no after-experience could remove, because it was compelled in fear and trembling to plunge under water. If a child be sufficiently robust to develop a good reaction, if it be over 2 years of age, and, above all, if it be not afraid, it may be bathed in the sea with advantage. If any of these conditions be wanting, sea-bathing for children is likely to be positively injurious. (Brit. Med. Jour.)

Attacks of cramp, to which even expert swimmers are liable, may arise from many causes. Where special nervous diseases do not exist, the so-called “cramp spasms” are, as likely as not, due to some irregularity in digestion, or to some imprudence in bathing at wrong times and seasons. Bathing after a full meal may induce so-called “cramps,” and it is to be feared that many a fatal case of drowning, attributed to some hidden nervous cause, has had a far simpler origin in digestive disturbances reacting on the nervous system, and through this system propagated to the muscles.

The ordinary rules—drawn up by the Royal Humane Society—which should be observed by all bathers, whether in fresh or salt water, and whether swimmers or not, are simple and readily borne in mind.

1. Never bathe within 2 hours after a meal.

2. Never bathe when exhausted or in ill-health. The practice of plunging into the water after exercise is to be thoroughly condemned.

3. Never bathe when the body is cooling after perspiration.

4. A morning bathe may be taken by those who are strong and healthy before breakfast on an empty stomach.

5. The young, or those who are delicate, should bathe 2-3 hours after a meal, and in the forenoon, if possible.

6. The signs which forbid open-air bathing altogether are chilliness and shivering after entering the water, numbness of hands and feet, and deficient circulation generally.

7. When the body is warm, bathing may be indulged in, provided undressing is quickly accomplished, and the body is not chilled before entering the water.

8. On leaving the water, dry and dress quickly. Standing about undressed, after leaving the water, is, under any circumstances, injurious.

9. Rather cut short, than prolong, the bathe. Swimmers possess the power of remaining in the water for a considerable time, in consequence of their active movements. But even in their case injury is often wrought by unduly extending the exercise. The slightest feeling of chilliness should be taken as a sign to leave the water at once.

It is a recognised fact that a sudden head douche of cold water is apt to cause giddiness in many persons from its effect on the brain-circulation, which forms in itself a peculiar part of the blood-system. Cases of persistent headache, often accompanied by giddiness and faintness, have followed sea and river bathing; these effects having disappeared when the practice of plunging the head below water was discontinued. Persons thus affected cannot do better than omit the head from the bath, and, in shower baths, stoop forward or lean backward and sidewise, so that the water shall fall on back, chest, and shoulders, but not on the head.

Hot Baths.—Concerning the bathroom, Edis remarks that whenever a bath is provided, it is generally left open, and forms a receptacle for dirt and dust, which is not always cleaned out when the bath is filled. He suggests that the bath be slightly lowered into the floor, and fitted with a hinged top, about seat-high from the floor, so as to keep the bath clear of dirt, and when not in use make it answer as a table or seat. A bathroom is often fitted up with cupboards for linen, and if the hot-water cistern be placed in the room on the floor level, or sufficiently high for use, or a coil of hot-water pipes be carried through, the linen cupboard with lattice shelves might easily be fitted over it, with closed doors of course, by which the linen would always be kept properly aired; and if the room be lined with tiles, there would be no fear of damp or moisture from steam condensing on the walls. The bath should be formed in a recess, with tile lining all round and overhead, and the recess might then be fitted with cupboards over, and drawers and useful shelves at one end, so as to provide storage-room for a large amount of spare clothing and linen, which it is often so difficult to find room for. A curtain drawn across the bath keeps it clean, and hides it from view when not immediately required.

Hot-air and Vapour Baths, Turkish Baths, &c.—The Lancet expresses a strong objection to that form of bath which involves the patient being in an erect or sitting posture, where the bath is used to produce perspiration; it is always possible that some amount of faintness or giddiness may be experienced by the bather even when the blanket or tent-shaped envelope is so effectively applied as to prevent the fumes rising to the mouth and being inspired. It is always far better, and ought to be a rule, that the patient should be in the recumbent position. With a properly constructed cradle-head, the bed-clothes can be raised and the lamp placed safely in the bed itself, the clothes being well tucked in round the neck and under the chin, so that nothing may reach the mouth. In this way the patient may enjoy the full benefit of a fairly high temperature without the least fear of faintness. There are, nevertheless, certain precautions which ought to be observed, and which are too commonly overlooked. (a) A thermometer with a long stem ought to be so placed that the bulb may be inside the clothes and the indicator-column visible outside. Such a thermometer might with advantage be supplied with the bath. It is always desirable to know the temperature of the atmosphere to which the patient is subjected. (b) The moment perspiration is induced there arises the question—How far ought it to be carried? If the purpose of the bath be to eliminate fluid or any product of tissue-waste from the body, there may be a need for the maintenance of the cutaneous perspiration for some time: but otherwise it is not, generally speaking, well to let the patient remain in the heat for more than 10 minutes; otherwise, the result can only be to saturate the bed-clothes with moisture, which will begin to cool as soon as the lamp is removed, and after the lapse of 20-30 minutes must place the patient in the perilous position of lying, perhaps sleeping, in a damp bed. A hot-air bath for ordinary purposes is better given in the morning than at night; or, if that be impossible, the patient should be removed to a dry bed with hot blankets. The body-heat can never be safely trusted to keep the clothes, which have been saturated with moisture by a bath, warm after the lamp is withdrawn. It is quite a different matter when the perspiration has been raised by the heat of the body itself. As a rule, the patient should be removed and wiped dry in about 20 minutes after the withdrawal of the lamp—that is, in ½ hour from the commencement of the bath. If the perspiration be acid, it is desirable to sponge the surface with hot water, in which about 1 dessertspoonful soda carbonate has been dissolved—say, in 1 qt. water. (c) If the case be one of rheumatism or gout, it must be recognised that by determining to the skin we are likely to get increased stiffness and surface irritation after each bath until the excrementitious material has been thoroughly eliminated. Overlooking this fact, patients, and sometimes practitioners, fail to persevere long enough with the baths, because, as it seems, each bath makes matters worse.

A simple form of hot-air or steam-bath for home use may be made as follows:—To the back of an ordinary wooden or cane-bottom chair fix an upright piece of wood, and to this at the height at which the neck of the sitter on the chair will be fix a hoop of cane or other material sufficiently wide to keep the cloth to hang from the hoop free from the shoulders of the sitter. Place beneath the chair a gas or oil lamp or two, if one does not give sufficient heat. If, now, a cloth be fixed round the ring sufficiently ample to reach the ground and close all round the sitter, a tent will be formed from the top of which the head of the sitter will project. Let the cloth overlap the ring freely, so as to permit of being pulled close to the sitter’s neck. Whilst taking this hot-air bath, the feet must be kept in a basin of warm water. If there is danger of a headache, a cold wet cloth on the head will prevent it. If a vapour bath is preferred, place a pan of water over the lamp, so that the water may boil.

Ellis & Co., of 47 Farringdon Road, London, have introduced a Cabinet Turkish Bath, which dispenses with chair, lamp, sheets, and covers. It is exceedingly simple, and consists of a neat cabinet (Fig. 127) made of well-seasoned wood, taking up a floor space of only 2 ft. 5 in. by 2 ft. 8 in., and large enough to admit the person comfortably. It is mounted upon castors, so that it may easily be moved from place to place on the same floor; and it is light enough to be carried if required. It is fitted with a foot-warmer, and with an adjustable seat, so that it can be used by children and by adults of different sizes. A book-rest is arranged conveniently, so that the time may be pleasantly occupied, and small doors are provided through which the hands may be passed in order to turn over the leaves of a book, or to wipe the face, or to remove a cigar from the mouth, &c. The bath is heated by gas, or by a special lamp in which spirit is burned. It may be managed with the greatest ease without the aid of an attendant, being, in fact, quite as simple as an ordinary sponge or sitz bath. It is only necessary to fill the foot-warmer with hot water, covering it with a piece of flannel, to light the lamp, and step into the bath with a towel round the neck to prevent the heat escaping too readily. Ample ventilation is allowed, so that the body is not exposed to the action of vitiated air, since this is constantly being renewed from outside. The bath constitutes, in fact, a small ventilated hot chamber, the time spent in which may vary from 10 minutes to ½ hour, according to pleasure. The prices of this bath range from 5l. 10s., as made in best pine, to 9l., in black walnut.

Management of Hot-water System.

Before entering into the details of the management of a hot-water system destined to supply baths, &c., it will be desirable to acquaint the reader with the general plan and principle of an apparatus, and to explain the cause of circulation, &c., as this will convey some idea of the subject to be treated, for although many possess an apparatus fitted in their residences, yet much practical information cannot be gained from it, as a major portion of the work is hidden from view.

Figs. 128 and 129 show two distinct forms of apparatus, both of which are at present in general use, and both of which even now nearly equally share the public favour, although No. 1 is the more modern and has been proved to be practically superior to No. 2, and is now nearly exclusively adopted by most firms who profess this work.

No. 1 is known as the cylinder system, and consists of a cylinder (a square tank is sometimes used where the pressure of water is light, tanks costing much less than cylinders of the same capacity) which is placed at the nearest position to, but above the level of the boiler. Two pipes connect the boiler with the cylinder, the upper pipe a is termed the “flow,” and is carried from the upper surface of the boiler to about 9 in. up the nearest side of the cylinder as shown, and the lower pipe b, known as the “return,” is carried from a lower position in the cylinder, under the “flow,” to within about 3 in. from the bottom of the boiler, either through the top, as shown, or entering at the back or side.

From the highest point in the cylinder is carried a pipe c, called the “rising main,” by the nearest or most convenient route to above the level of the cold-water cistern, and terminates either by being carried through the roof (as shown) or by being turned over the top of the cistern referred to (as shown in dotted lines). This pipe, when the apparatus is in use, is charged with water to a little above the level of the cold water in the cistern, and the pipe is open at the top end to admit of the free escape of steam, and on that account is sometimes called the expansion pipe; from this pipe is, or should be carried all the draw-off services to the various points at which they are required. In event of this rising main being carried to a considerable distance or height, it should be “returned” from any convenient point below the cold cistern (as shown in dotted lines at d); this will cause the water to circulate in this upper service and avoid the annoyance and waste caused by drawing sometimes a large quantity of cold water (which lies stagnant in single pipes) before the hot water is obtained. When this “return” is effected, the service is known as the “secondary flow and return.”

Another good use to which the return can be put is in event of any draw-off services being unusually long, as that shown at m to the dressing-room in the illustration, the return can be connected as shown in dotted lines, and will bring about the same good results as explained in “returning” the rising main.

The supply of cold water to the apparatus is either brought by a direct and distinct service from the cistern, or is branched from the nearest existing cold service, but in the latter case the existing service must be of good size, for reasons that will be explained later on. The cold supply should be provided with a stop tap f, which is found most convenient if placed near the cylinder, as it can then be used by workmen or others without their having to traverse the house, but this tap should have a loose key or handle, which should be kept by some responsible person to prevent its being interfered with by any one ignorant of its use. There should be also a tap provided at a convenient point, say g, to empty the cylinder when the boiler requires to be cleaned or any repairs effected, and this tap should have a loose key for the reasons before stated.

The chief advantage of this system is safety, the cook or user being unable to empty the cylinder, consequently should the water supply fail, the fire can be lighted in the usual way without risk, as in ordinary use it would take several days to boil away or evaporate the contents of the cylinder and boiler.

Another advantage gained by this system is that the cylinder being in such a warm situation, much less heat is lost by radiation, and by its being nearer to the boiler the circulation is effected more rapidly; and there are several other minor advantages to be gained by it, which, however, are not of sufficient importance to warrant detail here. The cold supply pipe h leads from the cistern i to the cylinder k; l is the boiler; m are draw-off service pipes with taps n in the various apartments where needed.

Fig. 129 is commonly known as the “high” or the “old” system. This consists of a square or rectangular tank a, which performs the function of a reservoir for the hot water in the same way as a cylinder, but instead of being situated near the boiler b, it is fixed somewhere above the highest draw-off service, but of course below the cold cistern c; it is commonly found in the roof or attic in proximity to the cistern, but these are cold and bad situations for it; it is more often found in the bathroom, enclosed in a casing or cupboard, which is thereby made an efficient airing closet, and serves somewhat to prevent loss of heat referred to before (and hereafter), and the presence of the tank in the bathroom, although occupying considerable space, is a source of warmth, no mean advantage in winter.

The tank a is connected with the boiler b by “flow” and “return” pipes d e, the same as the cylinder, but they are necessarily much longer; the draw-off services f are, or should be, all connected to the “flow” pipe d as shown, as the water in this pipe is the first to become heated as the water circulates or “flows” from the boiler to the tank; and an expansion pipe g (not called a rising main in this instance) is carried from the highest point in the tank a to above the level of the cold supply c, as in the cylinder system. There is no need to return this expansion pipe, but an unusually long draw-off service can and should be returned for the reasons before explained, and the method is to connect and carry the draw-off service from the flow pipe in the usual way and return it into the return pipe at a lower point, somewhat after the manner shown at h. Obviously the run or course of all pipes has to be adapted to circumstances, but it can be taken as an invariable rule that in correctly executed work “flow” pipes never descend and “return” pipes never ascend, but this will be more fully explained later on. In speaking of circulating pipes, the “flow” is recognised as running from boiler to tank (or cylinder), and the “return” from tank to boiler.

The cold-water supply i is carried and connected to the tank a in the same manner as to a cylinder, and provided with a stop tap k to save the necessity of plugging the pipe where it leaves the cold-water cistern.

The chief advantage of this system is obtaining hot water a little quicker (but in less quantity) from the time the fire is lighted, than in the cylinder system, as it can be drawn almost immediately it leaves the boiler; but as good results in this respect can be attained with the cylinder if the directions subsequently given are attended to; another advantage in this system is that it can be erected at less expense than the other, and the tank costs but little more than half the price of a cylinder. These advantages are more than counterbalanced by the disadvantages, viz. the easy means of exhausting the apparatus of water if the supply fails, the longer period occupied in obtaining a body of hot water, and the necessarily cold or cool situations of the tank and pipes, so causing loss of heat by radiation, &c.

A few lines may be here devoted to explaining the cause of circulation, which the generality of householders are totally unacquainted with. For the reader to fully understand the subject, he must first know that water is composed of extremely minute particles (molecules), quite invisible to the eye, which have the property of gliding over, under, around, to and from each other, as circumstances dictate, in we may say a perfectly free manner, almost entirely without friction or resistance. When the apparatus is charged and the fire lighted, the particles nearest the fire become heated and expanded, and are, bulk for bulk, rendered lighter than their fellows, and consequently rise to the top of the boiler; finding an outlet there they rise up into this, and continue to rise until they reach the highest limit, which in No. 2 system is the top of the tank, and in No. 1 system, the top of the cylinder, unless the rising main is “returned,” in which case it will be where this “return” commences. Immediately the expanded particles leave the heated surface of the boiler, other cold particles descend into their place and are heated and expand to follow their predecessors, and so it continues as long as there is heat applied to the boiler. The circulation is really a continuous stream of expanded (heated) particles of water ascending the flow pipe, and a corresponding stream of cold or cooler particles descending the return pipe, a natural and very simple means of automatically transporting the hot water from the heating chamber (boiler) to the reservoir (tank) and automatically providing a supply of cold water to be heated in its turn.

The specific gravity of water at the boiling point, compared with water at the freezing point, is as 21 to 20, i.e. 20 gal. of very cold water will balance 21 gal. of very hot water.

The following are the few general rules to be observed for the efficient, economic, and safe working of either description of apparatus.

Commencing at the boiler, it is very necessary that the flue under this be quite cleared of cinders and ash once daily, and the length of the flue should be ascertained, as they differ considerably, and many instances occur where these flues are scrupulously cleaned but only in half or three-fourths their length, and very quickly the accumulation at the end of the flue becomes hard and solid, and an inexperienced person would then consider it to be the wall which forms the boundary at the back of these flues; this stoppage of course effectually prevents the water heating as it should do. Another cause of the water failing to heat quickly is omitting to have the interior of the boiler cleared of the incrustation or deposit (commonly known as fur) that accumulates more or less according to circumstances that will be fully described later on; when this inner coating attains a moderate thickness it very naturally retards the heat in passing from the fire to the water, especially as it is a poor conductor. There is, however, a more important reason why this incrustation should be removed regularly, and that is, when the boiler is coated to a certain thickness (which coating is more or less porous according to the district) it prevents the water coming in contact with the iron, and the boiler plate, however thick, is soon destroyed the same as if it contained no water at all, or to use a more familiar illustration, the same as a kettle would be “burnt” if left on the fire without having any water in it; this is a serious result from the costly nature of the repair.

The general form of incrustation is caused by the lime or chalk (bicarbonate of lime generally) held in solution, being separated from the water and precipitated; this precipitation commences at a moderately low temperature and gradually increases as the temperature rises, and the whole (excepting a very small quantity) is deposited when the water boils. The incrustation varies very much in quantity according to the district, as before stated; it is generally what is known as hard water that has the greatest percentage of this depositable matter; in some favoured districts the water is so soft that no appreciable deposit occurs, whilst in others it is not safe to leave the boiler longer than a month without cleansing to keep it in good order. There is also a variation according to whether the water boils much or otherwise, therefore the only reliable plan is to have a good workman in after a certain period, and he can then decide whether the amount of incrustation is too great or whether it might be permitted to go longer, and how long.

With London water, boilers that are in ordinary daily use should be cleaned out every 6 months to keep them in really good order, but to avoid the trouble of remembering dates, &c., many good firms keep a register for this work.

The most important places in the boiler that need cleaning are the parts immediately where the fire plays, especially the angles, where the boiler plates are welded or joined—and careless workmen are apt to neglect these parts—as the deposit is very hard and stone-like at these places.

It may be said without exaggeration that three-fourths of the fractures that occur to wrought-iron boilers are due to excessive incrustation, i.e. want of regular cleaning or removal of deposit.

Incrustation does not occur (but to an extremely small extent) in boilers used for heating purposes only, as in this instance the same water is heated over and over again, and water only contains a certain quantity of lime in solution, which is all deposited when it first boils.

It might be mentioned that in some places the deposit is organic matter, and is found in the boiler much resembling a layer of mud; in such instances the water should be filtered for obvious reasons.

The tank, cylinder and pipes, and in fact the whole apparatus (excepting the boiler) will be rendered more efficient by being covered with some non-conducting material to prevent loss of heat by radiation. Radiation is an important feature occasionally, as very many instances are known of apparatus being a complete failure, solely by reason of the tank or pipes (or both) being in very cold situations (cold draughty roofs, stone passages, &c., &c.); and a moment’s reflection shows that loss of heat is really loss of fuel attended with certain inconveniences well known to many who are suffering with this trouble. The common non-conducting material used is felt in its various forms. Hair felt is the best, as will be readily understood, and can be obtained at many ironmongers and may be applied by any one; for pipes it should be cut and put on in strips, wound round spirally, and tied. Another method is to encase the tank and pipes and pack the casing with a non-conducting material, such as cow hair, slag wool, sawdust, &c., but it is most necessary that the casing be packed, otherwise the heated pipes will render the casing a flue which will draw in cold air and very materially assist in cooling the water, especially if the casing has open or badly fitted ends, in which case failure of the apparatus can be confidently anticipated.

In addition to the heat-saving properties, this covering also possesses the advantages of keeping the different places cool (an advantage for certain seasons only, excepting the kitchen) and saves the pipes from attack of frost, and under ordinary circumstances, if a small fire is left at night with the boiler flue closed, moderately warm water can be had for bathing before the fire is lighted in the morning; these two latter advantages are perhaps the greatest.

In reference to this subject, it is a great convenience if the range (if the boiler is in a range) is provided with a means of opening the fire, as, with an open fire a small quantity of fuel can be placed on it the last thing at night and it will burn in safety for a considerable time, and really hot water can by this means be obtained at an early hour in the morning if the apparatus is “insulated” as explained above.

If the felt is placed round the pipes and tank without casing it should be one or two layers thick, say about ½ in., so that the hand can scarcely perceive any heat when the apparatus is in full action; a single layer of felt will answer, but not so perfectly.

Boiler explosions are at all times most serious disasters, for not only is the damage very great, but if any living thing is moderately near at the time the result is almost certain to be fatal, and it is a much-regretted fact that three-fourths or nearly all the terrible accidents of this kind could have been avoided with ordinary care; the reason that this form of accident is so serious is that before the explosion takes place, the steam has to attain sufficient power to burst the boiler, which is from ¼ to ½ inch thick of wrought iron, compared to which the human body is a frail object, and suffers accordingly.

The causes of explosions at present known are, firstly, stoppage in both the circulating pipes, caused by frost or by the terrible practice of putting stop taps in these pipes, which prevents escape of steam generated in the boiler, and steam must and will escape if it bursts the boiler to effect its release.

Secondly, failure of water supply. This is sometimes caused by a hidden or unnoticed leakage, or in country residences where the water is pumped this failure is not an uncommon thing (but only rarely results in an accident). If the want of water is unnoticed for a time, the boiler will empty itself by evaporation and afterwards become red hot; should the water then run in, steam will be generated so rapidly that the pipe outlets will not be sufficient for its free escape, and the boiler bursts; all this happens in much less time than is occupied in explaining it, in fact so quick that there is no time for escape if any one is unfortunately near; this, however, under ordinary circumstances cannot occur with the No. 1 system.

There is another though rare cause of accident (which, however, once came under the writer’s notice) that may occur with either system, and that is the ends of the circulating pipes nearest the boiler becoming stopped by incrustation; this incrustation, as has been before explained, takes place in the greater proportion of boilers, and also to a less extent in the pipes, especially near the boiler, and in course of time the pipes will both become completely stopped, but the reason that accidents from this cause are rare is that abundant notice is given by the steam making a variety of unpleasant noises and sometimes violent shaking, in forcing its way through the partly closed pipes, but this noise must not always be confounded with the sounds produced when pipes are imperfectly run or “trapped” and contain air, but whenever noises are heard a practical man should be consulted at the earliest convenience, and if a tap is opened and no water should flow, after it has been open say one minute, the fire should be immediately extinguished and kept so until the reason of failure of water is discovered and remedied. No alarm need be experienced at the rumbling noise to be heard when the water is boiling, but this water has no need and should not be permitted to boil; when the noise is heard, 4 or 5 gal. should be drawn off, this will be replaced in the tank or cylinder by the same quantity of cold water, and the temperature will be reduced; the damper which regulates the boiler flue should be out only when the water is cool and requires rapid heating; even then it must not be pulled out so far that the flame, &c., roars as it passes under the boiler, as the boiler will not experience the full benefit of the heat.

It has been suggested by some authorities that to prevent the water in pipes becoming frozen (this may be considered the most likely cause of explosion) a tap or taps should be left a little open at night so that the water is kept in motion; this, however, cannot be relied upon in a really severe frost, and it is also a waste of water, which is a consideration where the supply is by manual power, &c. Another method suggested is to empty the whole apparatus every frosty night; this is a very good plan to save damage to pipes as well as prevent accidents, but there is the doubt that but few would care to practise this on account of the trouble, and there is a serious risk if it is forgotten to turn the water on until after the fire is lighted. Tolerable reliance can be put on felting or casing the pipes, but the most efficient remedy is to see that the boiler is fitted with a safety valve, which, as the name betokens, is a source of safety and most probably of comfort also; if it is not convenient to attach a safety valve direct into the boiler, it should be connected by a short length of pipe, which however is a weakness, as the pipe may eventually be stopped by incrustation, and on that account it should be of good size and should be cleared, if necessary, every time the boiler is opened for cleaning. Safety valves should always be fixed in sight so that they can be tested whenever desired. The working principle of a spring safety valve (which has general preference just now) is, firstly, a brass sealing which closes the opening leading to the boiler and is held in position by a spring and central pin, and the whole works in a strong brass case which is perforated with several good-sized holes; when the valve is fixed, the workman can and does set the spring (generally by a screw-down cap at top) so that it withstands about 3 or 4 lb. more pressure than the boiler is subjected to by the pressure of water; when by any reason an undue pressure is exerted inside the boiler it causes the seating to rise, and the steam and some water escape into the brass case and through the holes above referred to, and the boiler is relieved. The noise occasioned by this escape is very plainly heard, and notice is thus drawn, but the fire need not be extinguished.

It would be a desirable feature if every boiler fixed (except open ones) was provided with a valve, as it is purchasing freedom from risk at a low price (a few shillings only).

There is a common cause of complaint and annoyance in having at some taps to draw off a quantity of cold water that lies stagnant in the service pipe before the hot water can be obtained from the circulation; this is caused by the draw-off service being a long and single pipe, and can be only remedied by “returning” it something after the manner shown in the illustrations, and so cause the water to circulate along it; this trouble is not only a source of annoyance but a practical loss also, as for every quantity of hot water drawn a certain quantity is left in the service to get cold, and this happens every time the tap is used, excepting such taps as are in constant use, and the water only remains stationary 2 or 3 minutes, but this in domestic purposes only applies to the scullery service at certain hours in the day.

It may have come to many people’s notice that when some lever-handle taps are shut a noise and jarring in the pipe ensues; this is caused by the sudden stoppage of the flow of water when the pressure is considerable; when the vertical pressure is say 50 or 60 ft. (height of cistern above the tap) and the tap is opened, the water rushes out and gains a strong momentum; by turning the handle or lever of the tap the stoppage is so sudden that a shock is sustained almost the same as an object falling from a height being suddenly stopped by coming in contact with the ground; this concussion and noise is not only unpleasant but does harm, which is quickly noticeable with light lead pipe, which is either stretched or has protuberances formed upon it, and a continuance of the shocks or really blows will then cause it to split; it will be therefore commonly found that screw-down taps are used with lead pipe where any pressure exists, and the screw-down tap would meet with more favour but for an objectionable feature, which is the number of times it has to be screwed or unscrewed to shut and open it; but there are now made screw-down taps that open or shut with one turn, and these no doubt will come into more general use if found practically good and when the patent expires.

Retarded circulations arise from a variety of causes, amongst which may be mentioned incapacity of the boiler for the work, caused by the boiler not having sufficient heating surface; this is shown by the whole apparatus becoming fully charged with hot water late in the day after several hours firing; the only remedy is to reduce the work the boiler has to do or change the boiler itself. Another cause is by pipes being dipped or trapped. The flow pipe having an inclination or dip downwards, which causes the circulation to become air-locked, this causes noises in the pipes and shakings as the steam is passing or trying to expel the air; this air is eventually expelled, but occurs again when the apparatus is emptied and recharged in boiler cleaning, repairing, &c.; to remedy this the pipes must be traced up and the defect so discovered. Another cause is by incrustation in the pipes; this can be noticed by its gradual growth, also incrustation in boiler, but if boiler is kept clear as referred to earlier in the chapter, the pipes will keep in very fair order. The only remedy for furred pipes is to take them out and by heating and striking to dislodge the deposit; this costs as much almost as renewing the service; with care in regular cleaning it will not occur. Obstructions either stationary or floating are sometimes found in the pipes and retard circulation; these are generally caused by the workmen failing to look through the tubes before fixing them, or the obstruction may be in the form of sediment in rural districts, &c.; the only efficient remedy that can be suggested is to engage the services of an experienced hot-water fitter in any of the cases mentioned, as it lies beyond the power of the householder to remedy them.

130. Flow Pipe.