BAT 



.33 



HAT 



the human system ; in our explanation of which, we will 

 endeavour to be as concise as possible. We treat first of 

 cold ; in doing which it is necessary to distinguish between 

 the immediate primary action of cold on the organ or part 

 with which it is brought into contact, and the secondary 

 action, depending upon the organic activity residing in the 

 part, or that train of effects usually denominated re-action. 

 The primary effect is always the same, consisting in the 

 abstraction of heat from the part, and the consequent re- 

 duction of its temperature, while the internal development 

 of heat becomes greater, so that the organic life strives ever 

 to maintain an equilibrium between the conllicting powers, 

 in order that it may not be limited or disturbed in its 

 healthy action. Yet it must be remembered, that both the 

 external and internal degree of the primary action of cold, 

 as also the period in which it slowly or suddenly shows 

 itself, and the time, whether longer or shorter, that it lasts, 

 occasion a variety of effects, both in the part to which 

 it is applied, and those more immediately sympathizing with 

 it. as well as in the whole system. The degree of primary 

 action of cold can vary in endless degrees, from the lowest, 

 where it scarcely affects the sensibility, to the highest, when 

 it utterly destroys life. This difference of degree depends 

 upon the concurrence of several circumstances, partly re- 

 lating to the action of the cold itself, and partly to the nature 

 of the organic life upon which the cold operates. The essen- 

 tial conditions which must be here borne in mind are, that 

 the continual evolution of animal heat is closely connected 

 with the development or exercise of animal life ; and that 

 the power or extent of action of external media, having a 

 lower temperature than that of the animal they surround, 

 depends less on the absolute degree of their temperature 

 than upon the quantity of caloric which they can abstract 

 in a given time. 



The relative power and quickness of abstracting heat, 

 with which different external media are endowed, depend 

 upon different properties, such as their density, conducting 

 power, capacity for heat, &c., and display themselves through 

 the diversity of sensations which, at the same absolute tem- 

 perature, they occasion. Thus, air at the temperature of 65 

 Fahr. feels pleasant, while water at the same degree feels 

 somewhat cold. The organs of the body also differ in their 

 power of sustaining the same temperature ; hence, in the 

 employment of vapour-baths, it is of importance to know 

 whether the watery vapour is to be breathed or not, since, 

 where it is to he breathed, the temperature must be much 

 lower. The following table is given by Dr. Forbes as an 

 approximation to what may be deemed correct as a measure 

 ot sensation in the cases where water and vapour are used. 



As a full exposition of the subject of the temperature 

 of animals will be given under the article HKAT, ANI- 

 MAL, we must refer to it for further details, confining our- 

 selves here to remark that the ultimate action of cold, when 

 extreme, is a sedative to the nervous system, and alters the 

 circulation from external to internal ; and that moderate 

 cold continued causes the same consequences as severe cold 

 of short duration (See Beauprc On Cold, Edinb. 1826.) 

 Heat, on the other hand, is a stimulant to the nervous system, 

 and alters the distribution of the blood from internal to ex- 

 ternal. Taking these principles as our guide, we proceed 

 now to consider the different kinds of baths, and their action 

 on the system in different states both of health and disease. 



First, of water-baths. The common division is into cold 

 and warm ; but various subdivisions are formed, marked by 

 a certain range of temperature, which are designated 



1. The cold bath, from 40 to 65 



2. The cool 65 75 



3. The temperate 75 85 



4. The tepid 85 92 



5. The warm-bath 92 98 



6. The hot-bath 98 112 



We shall treat first of the cold-bath, as applied to the 

 whole surface of the body. 



A healthy person upon entering a cold-bath experiences 

 a sensation of cold, followed by slight shuddering, and if 



the immersion has been sudden, a peculiar impression on 

 the nervous system, called a shock. The skin becomes 

 cooler and paler, the respiration hurried and irregular, the 

 action of the kidneys increases and the bladder contracts. 

 In a few moments the colour and warmth return to the 

 skin, and a glow is felt, especially if assisted by rubbing the 

 surface. If the person remains more than five or ten mi- 

 nutes in the bath, the glow disappears, and paleness returns, 

 which again gives place, though less quickly and perfectly, 

 to a renewed glow. During the existence of the primary 

 action of the cold, the bulk of the whole body, but especially 

 of the more contractile parts, diminishes. Should the stay 

 in the water be greatly prolonged, no reaction ensues, but a 

 general feeling of chilliness prevails, with quick feeble pulse, 

 convulsive breathing, cramps of the limbs, or fainting. If 

 the person quit the bath after the few first minutes, as in 

 prudence he should, the blood returns to the surface, accom- 

 panied with a sensation of pricking, itching, and sometimes 

 throbbing of the arteries : the elasticity of the muscles being 

 increased, more animal power is felt, accompanied with a 

 general feeling of enjoyment. 



Very young or feeble individuals are either incapable of 

 bearing the shock, or the reaction is so slight that they can- 

 not endure to stay in the bath beyond a very short time. If 

 they unwisely stay or are held in the bath longer than one 

 or two minutes, the heat never regains its proper height, 

 the extremities remain contracted, and they, as well as the 

 lips, nose, &c., are of a livid hue. In such cases either 

 artificial means must be used to bring about reaction, or the 

 bath must be relinquished, as improper for such persons, 

 as we shall show at a future part of our observations. 



The phenomena just described generally accompany cold 

 bathing; and it is clear that we can recognize in them 

 a series of three or even four distinct actions ; viz., 1st, 

 The shock ; 2nd, The cooling effect ; 3rd, The contrac- 

 tion or astringent effect ; and, 4th, The re-action. Cold 

 bathing may be employed, therefore, in such a way as to 

 ensure the predominance of one action over any of the rest, 

 according to circumstances, where all are not desired. They 

 vary with the degree of cold and the suddenness of the ap- 

 plication, as well as from the body being plunged into the 

 water, or the water dashed against the body. Where the 

 shock, as a stimulus to the nervous system, is desired, the 

 water should be very cold, and where practicable should be 

 dashed against the body, or, if the contrary, the stay in the 

 bath should be momentary. This mode of using it may be 

 either general or local. It has been employed generally, i.e. 

 the whole body exposed to the action of the water, in mania, 

 with occasional success, and in the early stage of the com- 

 mon continued fever (under certain regulations, for which 

 see Currie's Medical Reports), sometimes with great success, 

 cutting short the train of morbid actions which constitute 

 the fever. It has been employed also in nervous affections, 

 accompanied with a convulsive action, or deficient action of 

 the muscular system, as in hysteria, in lock jaw (see Paper 

 by Dr. Wright, London Medical Observations and Inquiries, 

 vol. vi. p. 143) : in some cases of obstinate constipation, 

 dashing cold water on the person, or the cold bath fre- 

 quently repeated, has been of great service. 



Its stimulating effect is sometimes best procured by a 

 local application, in the form of a stream of water falling on 

 the head, from a considerable height. The simplest ex- 

 ample of this is the common practice of sprinkling the face 

 with cold water in case of a tendency to faint ; and in many- 

 diseases of the most dangerous character, it is a remedy 

 superior to any other. It is called the cold dash, or douche, 

 or douse, and is beneficially employed in fever, particularly 

 when the brain continues the seat of inordinate action of 

 the blood-vessels, after depletion has been carried as far as 

 prudence will allow. (See the instructive case of Dr. Dill 

 in Dr. Southwood Smith's Treatise on Fever,f. 398.) It re- 

 quires to be used with the greatest caution. Also in the 

 state of stupor or coma which occurs in the last stage of 

 hydrocephalus arutus, or water in the brain, it often succeeds 

 in rescuing the patient from imminent danger. (See Abcr- 

 crombie On Diseases of the Brain, first edit. 1828, p. 157.) 

 Its utility is well known in the East in rousing drunken 

 soldiers from their stupor so effectually as to enable them to 

 rise up and appear immediately on parade. In the melan- 

 choly and mania which overtake habitual drunkards it is of 

 great efficacy, and also in cases of loss of nervous power from 

 excessive mental exertion. In apoplectic stupor it has also 

 been very advantageously employed. In the sinking stage 



NO. 209. 



[THE PENNY CYCLOPEDIA.] 



VOL. IV.-F 



