of the Fishery Board for Scotland. 



223 



contains 19 per cent, of proteid matters, fat beef about 15 per cent, 

 lean mutton contains 18 per cent., fat mutton 12 per cent. It will be 

 seen from Table IV. that salmon contains 22*93 per cent, of proteids, and 

 that many of our common fish, ami notably the herring, mackerel, 

 and eel, contain very nearly as much proteid material as beef. 



The extractives of beef also contain nitrogen, but are only present in 

 small amount. They are nevertheless of great nutritive importance, 

 though their action on the system is not yet explained. They most pro- 

 bably act as stimulants, and the commonest preparation of them, namely, 

 beef-tea, can maintain the strength for weeks when no other form of 

 nourishment can be taken. The Normal Company in Aberdeen have 

 discovered that fish is capable of yielding an extract which compares 

 favourably with extract of beef both for flavour and nourishing properties, 

 and they have been manufacturing it on a large scale for some time past, 

 This shows that though little is known as to the chemical nature of the 

 extractives of fish flesh, they have nevertheless substantially the same pro- 

 perties as those of beef. 



Although it is very important to know that fish contains nearly as much 

 nutritive material as beef, it is if anything more important to ascertain 

 whether this wealth of material can be readily rendered available for 

 nourishing the tissues of the body. Very few investigations with this as 

 their object were undertaken prior to 1884, the most remarkable being the 

 experiments on digestion performed by Dr Beaumont on the Canadian 

 Alexis St Nieffe, who had an accidentally formed gastric fistula. The 

 Canadian was found to be able to digest most fish in less time than beef, 

 though the time taken varied considerably with the mode of preparation, 

 and no experiments were made with the raw flesh. Salmon trout, whether 

 boiled or fried, took an hour and a half, dry cured codfish boiled took 

 two hours, fried flounder took three hours and a half, while salted salmon 

 boiled took four hours. Beef took from two hours and three quarters to 

 four hours and a quarter, according to the previous preparation and the 

 condiments administered with it. In 1884 an extensive series of 

 experiments was undertaken by Messrs R. H. Chittenden and G. W. 

 Cummins,* with the object of determining the relative digestibility of fish 

 flesh in gastric juice. The method adopted in these experiments was 

 novel, and so were the results obtained, so that a short account of both 

 may not be out of place here. 



The method was that of artificial digestion, because of the incon- 

 veniences attending the natural method of making gastric fistulse in 

 animals, and also because of the greater accuracy which may be attained 

 by the former method. 



The juice used in the experiments resembled natural gastric juice as 

 closely as possible, and was prepared by dissolving 5 grammes of 1 pure 

 pepsin ' in 1 litre of a 02 per cent, solution of hydrochloric acid in 

 distilled water. 



Twenty-four kinds of fish were experimented with, and beef, veal, 

 mutton, lamb, lobster, crab, and frog's legs were tried under similar 

 conditions for comparsion. The flesh used in the experiments was usually 

 cooked by steaming for half an hour before being digested. 100 grammes 

 of each kind of flesh were taken, free from skin, fat, tendons, and bones, 

 and thoroughly minced. Two portions of 20 grammes each were taken from 

 this mass, and after being finely divided were placed in beakers containing 

 200 cubic centimetres of the digestive fluid. The beakers were placed 

 on a perforated tin plate in the middle of a chamber with a few inches of 



* Report of United States Commission of Fish and Fisheries for 1884, Appendix. 

 Published 1886. 



