DIGESTION 



233 



The following table by Roger gives the mineral composition of 

 the faeces in every 100 parts of the ash :* 



Roger observes that the ash of the faeces of herbivora contains 

 scarcely any alkaline carbonates. 



The amount of faeces produced in twenty-four hours varies 

 with the quantity and nature of the food given. We have 

 observed that on a diet consisting of 6 kilogrammes (approxi- 

 mately 12 pounds) of hay, 3 kilogrammes (6 pounds) of oats, 

 and 1 \ kilogrammes (3 pounds) of bran, the average amount of 

 faeces passed by fifteen horses during an experiment lasting seven 

 days amounted to 14 kilogrammes (approximately 29 pounds 

 13 ounces) in twenty-four hours, the faeces being weighed in their 

 natural condition — viz., containing 76 per cent, water ; the dry 

 material of this bulk of faeces is about 3-25 kilogrammes 

 (7 J pounds). More faeces are passed during the night than during 

 the day ; in the above experiment, during the twelve hours (6 p.m. 

 to 6 a.m.), the average amount passed per horse was 9 kilo- 

 grammes (approximately 18 pounds 3 ounces), while from 6 a.m. 

 to 6 p.m. the amount was 5-5 kilogrammes (11 pounds 10 ounces). 

 -The largest amount of faeces we have known a horse produce was 

 an average of 33 3 kilogrammes (73*3 pounds), weighed in their 

 natural state, in twenty-four hours ; the diet consisted of 6 kilo- 

 grammes (12 pounds) of oats, 1-5 kilogrammes (3 pounds) of 

 bran, and 12 8 kilogrammes (28 pounds) of hay.) In an experi- 

 ment carried on for several months with different horses, all 

 receiving 6 kilogrammes (12 pounds) of hay, and varying pro- 

 portions of bran and oats, the average daily amount of faeces was 

 12 kilogrammes (24 pounds). A horse will evacuate the contents 

 of the bowels about ten or twelve times in the twenty-four hours, 

 and the food he consumes takes on an average four days to pass 

 through the body. 



* Quoted by Ellenberger. 



