COMPOSITION OF FEEDING STUFFS, 1887. 207 



grind them, and after mixing the meal with other substances, 

 such as locust bean meal or maize meal, and perhaps adding a 

 small proportion of some condimental flavouring material, to 

 manufacture what are called compound cakes or improved 

 cakes. 



The improvement in the softness and texture, and also in the 

 palatability of the cake, is undoubted, but such mixed cakes are 

 still more deficient in oil than the hard-pressed cake which 

 formed the basis of their manufacture. Regarding the feeding 

 value of compound cakes in comparison with other concentrated 

 fodders, some experiments are wanted, and we have much to 

 leani on that matter. Considering the great variety of oil seeds 

 that are now available, such as palm kernel and candle nut, 

 containing as much as 50 and 60 per cent, of oil, there should 

 be no difficulty in manufacturing compound cakes of standard 

 composition ; but whether such compounds would be as econo- 

 mical feeding stuffs as linseed cake is a question that must be 

 decided by experiment. 



There is always a certain amount of risk in dealing with such 

 mixed substances, for they are apt to be very inferior mixtures. 

 The buyer does not see so well what he is buying, and he has 

 to depend very much upon the honesty and accuracy of the 

 manufacturer, or else to have his purchases put under strict 

 microscopic and analytical examination. Nevertheless, it must 

 be pointed out that there is no security against buying inferior 

 material in the purchase of what is called linseed cake. Even 

 what is called pure linseed cake may, and frequently does, con- 

 tain a considerable proportion of other matters which require 

 microscopic examination for their detection, and seeing is not 

 believing with linseed cakes any more than with bone meal. 

 The microscope gives most reliable information regarding the 

 kind of impurities contained in cakes, but it cannot be trusted 

 to give any sure gauge of their quantity. For that purpose 

 chemical analysis must be had recourse to. 



If we apply the test of chemical analysis to the " linseed cakes " 

 whose composition is given in the above table, we see that most 

 of them are mixtures. 



Their average composition is 24J per cent, of albuminoids and 

 lOf per cent, of oil ; but that is not the composition of genuine 

 linseed cake. There is a fair amount of oil, and if we may 

 regard them as representing the average supply, it would seem 

 that either the deficiency of oil that was complained of is now 

 being guarded against by manufacturers, or that farmers have 

 been careful to see that the cakes they bought were not deficient 

 in that constituent. There are only three samples that are much 

 deficient in oil, viz., Nos. 6, 8, and 13. No. 8 is a genuine hard- 

 pressed linseed cake, but the other two are not genuine. No. 6 



