550 EVOLUTION OF HEAT, LIGHT, AND ELECTRICITY. 



observation, some years since, in the Old Meath Hospital, having been 

 admitted on account of an enormous cancer in her breast, which was in an 

 advanced stage of ulceration, the edges being irregular and everted ; every 

 part of the base and edges of this cavity was strongly phosphorescent, the 

 light being sufficient to enable the figures on a watch-dial to be distinguished 

 within a few inches; and here also it appeared that the luminosity was due 

 to a particular exudation from the exposed surface. Three cases are re- 

 corded by Sir H. Marsh, in which an evolution of light took place from the 

 living body, without any such obvious source of decomposition ; all the 

 subjects of these cases, however, were in the last stage of phthisis ; and it 

 can scarcely be doubted that here, as in other diseases of exhaustion, in- 

 cipient disintegration was taking place during the later periods of life ( 80). 

 The light in each case is described as playing around the face, but not as 

 directly proceeding from the surface ; and in one of these instances, which 

 was recorded by Dr. D. Donovan, 1 not only was the luminous appearance 

 perceptible over the head of the patient's bed, but lumiuous vapors passed 

 in streams through the apartment. It can scarcely be doubted that it 

 was here the breath which contained the luminous compound, more espe- 

 cially as it was observed in one of the cases to have a very peculiar smell ; and 

 the probability that the lumiuosity was due to the presence of phosphorus 

 in progress of slow oxidation, is greatly increased by the fact already re- 

 ferred to ( 319), that the injection of phosphuretted oil into the blood- 

 vessels gives rise to a similar appearance. In repeating this experiment, Sir 

 H. Marsh states, that when half an ounce of olive-oil, holding two grains of 

 phosphorus in solution, was injected into the crural vein of a dog, a dense 

 white vapor began to issue from the nostrils even before the syringe was 

 completely emptied, which became faintly luminous on the removal of the 

 lights; and the injection being repeated with the same quantity, the expira- 

 tion immediately became beautifully luminous, resembling jets of pale- 

 colored flame pouring from the nostrils of the animal. And the luminosity 

 which has been occasionally observed in the urine, 2 may fairly be imputed 

 to an increase in the quantity of uuoxodized phosphorus which it seems 

 normally to contain; its liberation taking place at a more rapid rate than 

 its conversion into phosphoric acid, either through excessive excretion or 

 through impeded respiration. 3 A case has been recorded by Raster (loc. 

 cit.), in which the body-linen was rendered luminous by the perspiration, 

 after any violent exercise ; and here, too, the cause may be presumed to 

 have been the same. On the whole, then, we may conclude the occasional 

 evolution of Light from the Human subject to be the consequence (when 

 not an electrical phenomenon) of the production of a phosphorescent com- 

 pound at the expense of the disintegrating tissues ; which compound passes 

 off through one of the ordinary channels of excretion. 



4. Evolution of Electricity. 



442. When the vast variety of changes of condition to which the compo- 

 nents of the living body are subjected during the performance of its vital 



1 Dublin Medical Press, Jim. loth, 1840. 



2 (Jasper's Wochensehrift, 1849, No. 15. A case ha? been put on record (Biichner's 

 Repert., 15d. viii, p. 342), in which the urine and semen of a patient who was under 

 treatment lor impotence and spermatorrhoea, and who was employing phosphorus as 

 a remedy both internally and externally, were observed to be. luminous. 



1 The large proportion of intemperate subjects, timonu; those* who exhibit this phe- 

 nomenon, seems to confirm the view already expressed, that the habitual presence of 

 Alcohol in the blood interferes with the oxidation and elimination uf excrementitious 

 matters. 



