Chap. I. SELECTION BY MAN. 41 



Tlie great poAVcr of tliis j^rinciple of selection is not hj- 

 potlietical. It is certain that several of our eminent breeders 

 nave, even within a single lifetime, modilied to a large extent 

 the breeds of cattle and sheep. In order fully to realize -what 

 they have done, it is almost necessary to read several of the 

 many treatises devoted to this subject, and to inspect the ani- 

 mals. Breeders habitually speak of an animal's organization 

 as something quite plastic, which they can model almost as 

 thcv please. If I had space I could quote numerous passages 

 to this effect from highly-competent authorities. Youatt, -who 

 was probably better acquainted with the works of agricultu- 

 rists than almost any other individual, and who was himself a 

 very good judge of an animal, speaks of the principle of selec- 

 tion as " that Avliich enables the agriculturist, not only to mod- 

 ify the character of his flock, but to change it altogether. It 

 is the magician's wand, by means of which he may summon 

 into life whatever form and mould he pleases." Lord Somer- 

 ville, speaking of what breeders have done for sheep, says : 

 " It would seem as if they had chalked out upon a -wall a form 

 perfect in itself, and then had given it existence." In Saxony 

 the importance of the principle of selection in regard to merino 

 sheep is so fully recognized, that men follow it as a trade : the 

 sheep are placed on a table and arc studied, like a picture by 

 a connoisseur ; this is done three times at intervals of months, 

 and the sheep are each time marked and classed, so that the 

 very best may ultimately be selected for breeding. 



What English breeders have actually eifectecl is proved by 

 the enormous prices given for animals with a good pedigree ; 

 and these have now been exported to almost every quarter of 

 the world. The imjirovement is by no means generally due 

 to crossing diilerent breeds ; all the best breeders are strongly 

 opposed to this practice, except sometimes among closely-al- 

 lied sub-breeds. And when a cross has been made, the closest 

 selection is far more indispensable even than in ordinary cases. 

 If selection consisted merely in separating some very distinct 

 variety, and breeding from it, the princi^Dlc would be so obvi- 

 ous as liardly to be worth notice ; but its imjiortance consists 

 in the great edec't produced by tlie accumulation in one direc- 

 tion, during successive generations, of diiferences absolutely 

 inappreciable by an imeducated e^-c — diflerences which I for 

 one have vainly attempted to appreciate. Not one man in a 

 thousand has accuracy of eye and judgment sufficient to be- 

 come an eminent breeder. If gifted with these qualities, and 



