STRUCTUEE OF DOMESTICATED ANIMALS. 299 



breeding of which we would desire to influence, all those 

 observations which have been made upon a few. 



I should like presently to make some remarks as to the 

 kind of training necessary for this, that you may not imagine 

 that the fii'st enthusiast can go to work and do it. It requires 

 a long training to be prepared to look at an egg, to be pre- 

 pared to see how it grows ; but before I make any such 

 remarks, I would say a few words more concerning the forma- 

 tion of the germ, so that you may see what an interesting 

 field of observation is now open to the student ; open , not 

 yet cultivated ; by no means cultivated to the extent desirable 

 in order to make the knowledge in any way useful in practi- 

 cal life. There is that condition necessary to all knowledge, 

 that it should be acquired, not only in its general features, in 

 order to be useful, but that it should be brought to a point 

 where it shall be really applicable to any practical purpose ; 

 and a great deal of the difficulty in scientific investigation 

 arises from the fact, that while it is easy to study, to a cer- 

 tain extent, it is not always easy to carry our knowledge to 

 the point where its application becomes easy or even practi- 

 cable. And I would say, to exonerate science from its fail- 

 ure to make itself more generally popular and practical, that 

 the mental qualities required for investigation are not the 

 same as the qualities required for practical application. You 

 know too much of practical life to need to be told that the 

 importers who bring to your manufacturing establishments 

 the raw materials are not those who make the cloth for your 

 clothes ; or that those who import the raw materials with which 

 all the various manufactures are produced are not likely to be 

 themselves manufacturers ; and the ability of the one excludes 

 very often the ability of the other. In scientific matters this 

 is perhaps more extensively the case than in practical pur- 

 suits, so that a class of men must be educated who will take 

 up knowledge where the scientific man leaves it, and carry it 

 where the man of business, oi* the practical man, requires it. 

 I could mention many a case in which scientific men have 

 injured themselves in their attempts to derive profit from 

 their scientific work. That will happen again and again when 

 scientific men enter into the arena of practical life. You 

 must allow them to work in the field for which they were 



