MB. MABTINEAU ON EVOLUTION. 313 



who come into Germany to work upon the railways always eat cheese 

 with their staple food, maize. Other populations derive all their nutri- 

 ment from 800 parts of bread and 100 of meat, besides potatoes and 

 hei-rings. All these facts are in full accord with the experiment made 

 on the dog, which lost weight on 800 parts of bread, or on the same 

 with extract of meat, and finally died in convulsions. 



On this subject we have the valuable researches of William Stark, 

 datino- from 3 789. He tried experiments upon himself as to the 

 relative value of different kinds of food. For 42 consecutive days he 

 lived on 556 to 849 parts of bread and 900 to 1,800 water per day. 

 Meanwhile he lost 17 lbs. weight. Then he took 736 to 962 of bread, 

 113 to 226 sugar and 900 to 1,300 water, and in 28 days lost 3 lbs. 

 But he gained with 849 bread, 1,800 milk and 1,300 water. Hence it 

 will be seen that prison-fare of bread-and-water is justly to be re- 

 garded as a punishment. In fact, the sentence condemning a man to 

 live four weeks on such fare is in Danish law equivalent to sentence 

 of death, and in Denmark no case has ever occurred of a culprit sur- 

 viving his punishment. 



Of course, Prof. Voit is far from condemning the use of vegetable 

 substances for food ; but he insists upon it that they must be combined 

 with proper nutritive elements in assimilable form, in order to keep the 

 body vigorous. These vegetable substances are deficient in albumen, 

 and nothing can supply it better than flesh-meat. It is also advisable 

 to substitute, for a part of the mass of starchy material, animal or 

 vegetable fat. It is not denied but that one may sustain life on purely 

 vegetable fare. The only conclusion the author insists upon in this 

 first portion of his essay is, that the alimentation of man is always best 

 secured, as regards azotic and fatty food, when the latter is got from 

 animal matter, and oftentimes the elements in question cannot be de- 

 rived from any other source. Chemistry alone will not account for 

 this disparity. The principles of which we speak do not differ from 

 one another chemically in their origin. It is only physiological ex- 

 perimentation, with the living being as the reactive agent, that can 

 show these differing properties, as we have seen. This is a point of 

 great importance. The question of nutritive salts, which we are next 

 to consider, is no less important. Revue Scientijique. 



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MR. MARTINEAU ON EVOLUTION. 



Br HEEBEKT SPENCEE. 



THE propriety of dealing with the leading criticisms that have been 

 made on the general doctrine set forth in " First Principles " more 

 especially criticisms on the metaphysical aspects of that doctrine has 

 been from time to time pressed upon me. Having recently been led to 



