192 ANNUAL OF SCIENTIFIC DISCOVERY. 



been shown that within the bodies of carnivora, a very considerable 

 amount of oxygen is produced from water ; and that, under given cir- 

 cumstances, a powerful process of decomposition is set up, resolving the 

 water into its constituent parts, its oxygen serving for the formation of 

 carbonic acid, and the hydrogen (which often exceeds the volume of 

 the animal in quantity) being discharged by expiration. 



Microscopic Use of Magenta Dye. Magenta dye can be employed 

 in microscopic research to great advantage, to tinge blood-globules or 

 animal cells. It causes nuclear structures to be distinctly displayed. 



Pigments from Coal Tar Colors. The practical application of the 

 beautiful colors extracted from coal-tar has recently received a farther 

 extension, in the discovery, by a French chemist, of a method whereby 

 pigments can be prepared from the dyes suitable for use in oil paint- 

 ing. The process consists essentially in mixing a solution of the coal- 

 tar color in an alcoholic solvent, with a solution of pure white soap in 

 hot water. To this is added alumina in a gelatinous state (prepared 

 from alum), when the colors are precipitated in connection with the 

 alumina. By these means, and especially by the assistance of an animal 

 matter in a soapy state, the colors are rendered solid and durable, and 

 are applicable for painting. When the blue and yellow products are 

 combined, a fine green is obtained, and the mixture of red and yellow 

 produces an orange color ; and, by the mixture of the different colors, 

 all varieties of tints can be procured. The richness of these colors is 

 unequalled ; and it is claimed that they remain unchanged when ex- 

 posed to light. 



Poisoning by Nitro-Benzole. By a paper communicated to the 

 Royal Society (G. B.) by Dr. Letheby, it appears that if a dose of ni- 

 tro-benzole be not too large, its poisonous action will not be imme- 

 diately apparent, but it may " destroy life by a lingering illness, which 

 shall not only defy the skill of the physician, but shall also baffle the 

 researches of the jurist." After death, the blood of animals so killed 

 is black and turbid, and the large organs congested, and no nitro-ben- 

 zole can be discovered, if sufficient time has elapsed, as it will then be 

 converted into aniline. Such facts show the necessity of having medi-- 

 cal men well trained in chemistry. Aniline produces symptoms very 

 similar to nitro-benzole. The conversion of the latter into the former 

 takes place in a dead stomach, or by contact with putrid flesh for sev- 

 eral hours. ' 



Effects of Suppressed Action of Skin. Edenhuizen has performed 

 some experiments on rabbits, sheep, a dog, and other animals, for the 

 purpose of ascertaining what changes take place in the organism when 

 the action of the skin is suppressed. When one-eighth to one-sixth of the 

 skin of an animal was covered with glue, oil-color, varnish, gum, tar, etc., 

 it was sure to die of the effects. Edenhuizen infers from his researches 

 that in the healthy state, a small quantity of nitrogen in a gaseous form 

 is given off by the skin, and that this function being suppressed, the 

 nitrogen is retained in the blood in the form of ammonia, which is then, 

 deposited as triple-phosphate in the subcutaneous areolar tissue, and in 

 the peritoneum. The nitrogenous compound retained in the blood 

 acts as an irritant to the nervous system, producing rigors, palsies, 

 cramps, and tetanic attacks. 



Secretion of Urea and Chloride of Sodium. - - Dr. Emil Becher, as- 



