59; 



SKIN, DISEASES OF. 



SKY. 



598 



The treatment of eczema must he adapted to the causes which have 

 produced it. According to the general elate of health of the person 

 attacked, the disease will be either acute or chronic. Slight cases of 

 acute eczema require only a simple treatment ; a light diet, saline pur- 

 gatives, and cooling or emollient applications to the part being all that 

 is required. In some eases the inflammation is great and the pain 

 intense, and where this occurs bleeding and a more active general 

 treatment should be had recourse to. Chronic eczema is much more 

 difficult to treat. The general health demands attention, and altera- 

 tives and tonics, according to circumstances, are demanded. Astringent 

 lotions and ointments, such as the preparations of silver, zinc, alum, 

 &c., may be used ; sulphurous baths, and various mineral waters have 

 also been recommended in old chronic cases of this disease. The 

 tincture of cantharides and the preparations of arsenic have also been 

 employed in the chronic forms of eczema. 



Miliaria ^Febris miliaris, Miliary Eruption) is also a vesiculous disease 

 of the skin, and is described as contagious. It is accompanied with 

 inflammation of the gastro-intestinal mucous membrane, and is accom- 

 panied by profuse sweating. Miliaria as an epidemic and independent 

 disease is only seen between the 43rd and 49th degrees of latitude, and 

 its existence has been doubted by some nosologists. It frequently 

 accompanies other diseases, and retires with the cessation of the disease 

 which it attends. When the fever accompanying it is slight it requires 

 little treatment. Gentle purgatives and demulcents will be found 

 sufficient. In the epidemic form, however, it is often a formidable 

 disease, and requires the same treatment as other epidemic contagious 

 fevers. 



Ku/,ia is a bullous disease accompanied with small bulla>, the bases 

 of which are inflamed. The bulls are not numerous but flat and full 

 of a serous fluid, which becomes thick, puriforui, or sanguinolent, and 

 drying up forms blackish thin or prominent crusts. It is commonly 

 developed on the legs, sometimes on the loins or thighs. It attacks 

 children that are of a delicate constitution, and persons weakened by 

 other ^ i<u The scrofulous are peculiarly liable to it, and it comes 

 on after hard living, insufficient food exposure to cold, and vicious 

 courses of life. It is generally indicative of an imperfect state of 

 nutrition, and the treatment consists not so much in applications to the 

 diseased skin, as in giving tone to the system by nutritious food, and 

 tonic and alterative medicines. 



Ectliyma (Pustulous Scale) is a non-contagious inflammation charac- 

 terised by large pustules raised upon a hard circular base of a bright 

 red colour. The pustules are of the largest size, the phlyiaciw of 

 Willan, so that ecthyma bean the same relation to pustular diseases 

 that rupia does to vesicular ones. In some stages in fact it is difficult 

 to distinguish one of these diseases from another. Willan describes 

 four varieties of ecthyma, but Rayer recognises but two, acute ecthyma 

 and chronic ecthyma. Acute ectbyma is a comparatively rare disease ; 

 it generally appear* on the neck and shoulders, and runs its course in 

 a few days This form requires little treatment ; light diet, diluent 

 drinks, mild purgatives, and warm or cold applications to the part will 

 suffice. 



In chronic ecthyma the same kind of pustules appear, which dis- 

 charge their contents in the course of two or three days, leaving behind 

 them thick brown adherent crusts, which sometimes fall off, leaving an 

 ulcer behind, but more frequently leaving a cicatrix. This form of 

 the disease comes on in scrofulous and debilitated subjects, and is 

 frequently modified by a syphilitic taint. Just in proportion to the 

 intensity of the constitutional derangement will be the duration and 

 extent of the disease. In its treatment the general health must be 

 especially attended to ; it is more a disease indicating a want of action 

 th in increased action, and alteratives, tonics, nutritious diet, change 

 of air, and sea-bathing are more beneficial than the opposite kind of 

 treatment. 



Arne (Uutta rosacea, Hose-drop) is a chronic inflammation of the 

 skin characterised by an eruption of small pustules surrounded by 

 a hard and inflamed base. They are generally observed on the 

 cheeks, nose, and forehead, and sometimes on the ears and neck. The 

 pustule* are sometimes single, constituting the simple form of the 

 disease ; at other times they become hardened and the whole skin 

 becomes red, when the disease has different designations. This disease 

 has its origin in the oil-tubes, and arises from an obstruction to the 

 performance of their functions, which produces inflammation. The 

 oil-tubes of the face are very liable to obstruction from exposure 

 to the air and other causes, and may be freqvieutly observed tipped 

 with a little black spot, and when pressed they give out a quantity 

 of their oily secretion in the form of a little maggot. They were 

 at one time supposed really to possess an independent animal life. 

 Although this is not the case with the masses of oil in question, 

 it is now known that a little acarus takes up its abode in these oil 

 tubes, and is well known to zoologists under the name of Demodex 

 Folliculorurn. This little insect may then in some instances be the 

 exciting cause of acne. 



In the treatment of acne, regard must be had to the general health. 

 It U frequently connected with a diseased state of the gastro-intes- 

 tinal mucous system, which requires attention. Where it is connected 

 with general debility from a rapid growth, or with a scrofulous constitu- 

 >nics and alteratives with sea-bathing and regular exercise will 

 be found of service. As external applications, the preparations of 



copper, zinc, and mercury, have been found most efficient. Where the 

 face is much swelled and inflamed, fomentations will be of service pre- 

 vious to the use of the astringents. 



Lichen is a papulous disease, characterised by the simultaneous or 

 successive eruptions of red itching pimples, scattered or disposed in 

 groups over the whole body. It is in the adult what Strophulus is in 

 the child. 



Lupui is a disease of the skin which, although it usually attacks 

 the face, may appear on any other part of the body. It is generally 

 attended with inflammatory action and with more or leas enlarge- 

 ment of the parts attacked. It terminates in ulceration, which on 

 account of its tendency to destroy the tissues which it attacks has got 

 for this disease the name of " wolf." The ulcer is also called the 

 " rodent ulcer," and the term noli me tangere has been applied to it. 

 The disease may be superficial or it may penetrate more or less 

 deeply, destroying whatever tissues it attacks. There is no doubt 

 about the resemblance of this disease to cancer, especially that form 

 called epithelial. It is, nevertheless, so strongly separated that it 

 would be utterly inconsistent with the present knowledge of the 

 nature of cancer to regard it as originating in the same state of the 

 system. [CANCER.] The condition of the system and the nature of 

 the ulceration rather point to the scrofulous diathesis as the originator 

 of this disease. 



In lupus no pathological elements can be discovered resembling 

 those of cancer. If removed it does not recur, and there is no ten- 

 dency to the production of the same disease in the lymphatics as in 

 cancer. It is therefore a much less formidable disease. Nevertheless, 

 the progress of the ulceration in miny cases of lupus is sufficiently 

 alarming and demands constant attention. 



The treatment must be both local and general. In the local treat- 

 ment removal by the knife is mostly out of the question, on account 

 of the extent of surface involved. According to the tendency exhibited 

 by the ulceration to spread a severe or mild system of cauterisation 

 should be pursued. Sometimes the application of sulphate or acetate 

 of zinc or nitrate of silver is sufficient to stimulate the parts to 

 assume a healthy action ; whilst at others more violent applications, as 

 the chloride of zinc and tannic, nitric, or hydrochloric no MS, are to be 

 recommended. General treatment is frequently very emcacious, and 

 this according to circumstances. In cases of tuoerculosis of the 

 system cod liver oil and quinine, and iron may be used with advantage. 

 In another set of cases arsenic has beeu found efficacious, whilst 

 perhaps a larger number are benefited by preparations of iodine. 



SKIN-DRESSING. [LEATHER MANCJFACTCBE.] 



SKY is the name commonly applied to the infinite space which 

 surrounds the earth, and of which the visible portion, above the 

 horizon of a spectator on any part of the earth's surface, appears to 

 have the form of a concave segment less than a hemisphere. 



The earth is surrounded by the atmosphere, which is charged with 

 vapours and terrestrial particles ; and by the reflections which, in con- 

 sequence, the rays of light experience in passing to the spectator, and 

 the absorption which they undergo in their long transit of the atmo- 

 sphere when the sun is near the horizon, the sky assumes the variously- 

 coloured tints under which it is seen. 



It is known from many experiments that pier air is devoid of colour ; 

 and the observations of M. de Saussure (' Voyages dans les Alpes,' 

 torn. 4, p. 289) have established the fact, that, in an atmosphere free 

 from vapours, such objects as mountains covered with snow, when 

 seen by a spectator at a distance of 20 or 30 leagues from them, by 

 light which is merely transmitted through the air, appear to be white : 

 the same philosopher has observed, however, that at times when the 

 sun is seen to set behind a mountain so covered, the blue rays reflected 

 from the sky to the mountain, and from thence to the spectator, cause 

 the mountain to assume a blue colour, the other light with which 

 the mountain is illuminated not being strong enough to overpower 

 the blue reflected rays. 



When the sun has considerable elevation, the rays of light which pass 

 through the earth's atmosphere almost perpendicularly to its surface, 

 undergo scarcely auy change of direction ; but, with respect to the 

 light from the sun which enters obliquely into the atmosphere, the 

 violet and blue rays are partially arrested in their course, and are re- 

 flected in abundance to the earth ; they thus, when thu atmosphere is 

 nearly free from clouds, give to the parts of the sky which are remote 

 from the apparent place of the sun an azure tint. 



The blue colour of the sky about the zenith increases in proportion 

 as the sun is nearer the horizon ; and, at the same time, the blue rays 

 in the beams of light which traverse the atmosphere in directions 

 nearly parallel to the horizon are absorbed, so that it is chiefly those 

 of less refrangibility, such as the yellow and the red, that arrive at 

 the eye of the spectator : in consequence of this the sky near the 

 horizon, on the side which is towards the sun, appears to be highly 

 tinted with those colours. 



Many of the blue rays, after reflection from the upper parts of the 

 atmosphere, are, however, absorbed in passing down to the earth ; 

 and lurther, it seems probable that in that portion of the reflection 

 which takes place at a great elevation the blue rays are reflected in 

 larger proportion compared with other colours than lower down; 

 and hence it is that the blue tint of the sky is found to increase in 

 intensity as the spectator ascends above the general surface of the 



