FLESH-FORMERS IN THE DIET OF THE HORSE. 513 



Explanation of some difficulties in the foregoing views. 

 Several difficulties, apt to startle the uninitiated reader, occur 

 in Professor Playfair's memoir. To make his observations 

 available in a work of a popular character like ours, it may be 

 worth while to attempt to remove some of these. Professor 

 Playfair's plan is excellent, nor is its excellence affected by 

 any objections that may be started to some of its details. 



To go back to the case of the food required respectively by 

 the horse at rest and the horse under labour (p. 508). He says, 

 in 12 Ib. of hay and 5 Ib. of oats there are 29.2 oz. of flesh- 

 formers. As the composition of hay does not occur in Pro- 

 fessor Playfair's table, it must be sought out in some other 

 table. In one of Johnston's tables the amount of flesh-formers 

 per cent in hay is given at 9.3. We have thus the numbers 

 100, 9.3 per cent, and the quantity of hay concerned, 12 Ib. or 

 192 oz. ; from which, by the rule of three, we find the pro- 

 portion of flesh-formers in the latter in ounces : as 100 is to 

 9.3, so is 192 to 17.85 oz. 



Again, we find the proportion of albuminoid principles or 

 flesh-formers in oats to be 15.4 per cent. Whence, in like 

 manner, the proportion in 5 Ib. or 80 oz. is found, 100 : 1 5.4 

 :: 80 : 12 oz. 



Thus, to omit the fraction, the 17 oz. of flesh-formers in 

 the 192 oz. of hay, and the 12 oz. of flesh-formers in 

 80 oz. of oats, make the quantity of flesh-formers in the 

 food of the horse at rest. Again, in the estimate of the flesh- 

 formers in the food of the horse under labour, the quantity 

 of hay being now 14 Ib. or 224 oz., the proportionals are 

 100 : 9.3 :: 224 : 20.8 oz.; and the oats being 12 Ib. or 

 192 oz., the proportionals are 100 : 15.4 : : 192 : 28 oz. 

 In beans the percentage of flesh-formers is given in Playfair's 

 own table at 27 ; hence 100 : 27 : : (2 Ib.) 32 oz. : 8 oz. ; the 

 sum of which number of flesh-formers in the working diet 



2K 



