1894- SOME NEW BOOKS. 383 



done we should not in the second edition see the wild goat of Persia 

 described and figured on page 52 of vol. ii. as Hircus agagrus, although 

 alluded to on page 321 by its proper title of Capra agagrus. Neither 

 should we find the saiga mentioned on page 44 of the same volume, 

 and the chamois on page 176, under the generic name oi Antilope. 



These are, however, but trifling blemishes in a most excellent 

 work, which will long be the standard on the subject of which it 

 treats, and reflects credit alike on its editor and its contributors, as 

 well as on the artists and publishers. 



The Chemistry of Animals. 



The Essentials of Chemical Physiology for the use of Students. By 

 W. D. Halliburton, M.D., F.R.S., F.R.C.P., Professor of Physiology in King's 

 College, London, etc., etc. Pp. i66. London : Longmans, Green & Co., 1893. 

 Price 5s. 



In the records of research and in advanced treatises the most certain 

 and the newest ^^discoveries are so held in solution that only an expert 

 can detect them. But when a brilliant investigator and competent 

 teacher like Dr. Halliburton writes a text-book for students, we 

 expect to find that his mind has acted on the confused details of his 

 science so as to precipitate and render obvious the most important 

 truths. It requires small effort to see that Dr. Halliburton regards it 

 as of the first importance to impress on students that in chemical 

 physiology they are concerned with living organisms. Natural 

 Science from time to time has called attention to the growth of what 

 is called " Vitalism " in physiology, and here in that citadel of the 

 mechanical school — the chemistry of the animal body — one finds the 

 new doctrine entrenched. Consider what one was taught even a few years 

 ago. The body was a collection of specialised organs, each organ with 

 its own function or functions. The blood was a mechanical channel of 

 connection between the organs. The food was taken into the alimen- 

 tary canal and the various digestive juices acted upon it so that 

 insoluble substances were turned into soluble. These latter passed 

 by osmosis into the blood directly, or through the lacteals. By the 

 blood they were handed on to the different organs, in each of which 

 certain chemical processes went on. In the lungs oxygen diffused in, 

 carbonic acid diffused out, and the reverse process took place in the 

 tissues. Wherever a direct mechanical or chemical comparisDn 

 could be made it was adopted as an explanation. Elaborate tables 

 abounded, showing the transformation of so much food material into 

 so many grammes of fat and glycogen and proteid ; calculations were 

 made showing the work to be expected from the oxidation of so 

 much proteid and carbohydrate and the corresponding production of 

 waste products. 



Here all these matters are in the background, being replaced by 

 the microscopic appearances of the cells and tissues ; and the idea 

 that all the processes are vital processes occurring in living proto- 

 plasm is insisted on. In digestion, no doubt, insoluble starches are 

 turned into soluble sugars, insoluble proteids into soluble pep- 

 tones ; fats are emulsified and saponified. But these do not 

 diffuse into the blood ; they are " eaten " by the living cells of the 

 alimentary canal, and these, neglecting diffusibility or indiffusibility, 

 select what they want not even systematically but with varying 

 caprices. Indeed if soluble peptone be injected into the blood, 

 into which it used to be thought to soak, poisonous effects 



