BREEDS AND THE PRINCIPLES OF BREEDING. 427 



Woonsocket, R. I., commenced breeding the improved Suffolk pigs more than twelve years 

 ago from two animals of this breed which he bred without taking in any new blood, breed 

 ing in every conceivable way, mother and son, father and daughter, and brother and sister, 

 and raised an average of about one hundred and ten pigs per year; in ten years raising 

 eleven hundred. Among those eleven hundred pigs there has not been one that was de 

 formed, every one has been perfect. 



Mr. Cheever says respecting this case: &quot;Perhaps I ought to state that this gentleman 

 has a theory of his own. He always keeps a male for the service of his neighbors, but he 

 never allows his neighbors animals to be served until he has done using him himself. 

 His breeders are kept in the very best health possible, with his knowledge and ability, and 

 after he has used them himself, then his neighbors have the advantage of them. He accounts 

 for his success in that way. That is a case of more thorough inbreeding than almost any 

 other I know of in the country.&quot; 



This is certainly a very exceptional case, for even in ordinary breeding it is unusual to 

 raise a hundred pigs without having deformities of some kind; and more especially are such 

 deformities liable to occur in close inbreeding. 



Crossing. Cross-breeding is the coupling of two animals of different and distinct 

 breeds. The use of a pure-bred male upon a mongrel or grade female is not a case of cross 

 ing, but the term is frequently used, as between two strains of blood, or two families of the 

 same breed. It frequently happens that the breeder may be desirous of engrafting a certain 

 peculiar excellence of one breed or strain of animals upon another. As a general rule, the 

 more widely the two breeds or strains differ, the more variable will be the offspring of 

 parents thus crossed, since there will be a peculiar tendency to reversion, and the hereditary 

 force is weakened, while the nearer alike the two breeds crossed, the less variable will the 

 offspring be, and the easier will it be to breed true to the general characteristics. It is a 

 noticeable fact, that the second, third, and often several successive generations, will prove 

 more variable when mongrels or grades are bred, than the offspring of the first cross. Dr. 

 Sturtevant says in this connection: 



&quot; In crossing animals of the same race we have a union of forces under the laws of 

 breeding, but on account of our little knowledge concerning the relative strength and the 

 combined action of the forces we are using, the results are apt to be exceedingly variable. 

 When two forces meet in antagonism, each is modified and changed according to the law of 

 mechanics, but neither force is obliterated; the effect of the struggle remains, while the 

 forces may be in abeyance. Like the circular ripple of the pebble dropped in the water of 

 smooth surface, the effect is ever acting, ever extending, and we thus have a series of actions 

 modifying changes for all time. Characters in an animal are never obliterated, but may dis 

 appear from our view. &quot;We have, in crossing, a means for the modification of race, by pro 

 ducing changes through direct antagonism of force. &quot;We also have in free crossing a moans 

 for the preservation of uniformity between members of the same race. Like a two-edged 

 sword, the law of crossing cuts both ways, according as its principles are applied, and under 

 the government constantly of the great law of nature, that of the persistence of force. As 

 the antagonism of forces may be considered in the light of a mutual absorption, other forces, 

 too weak to otherwise appear in a form recognizable to us, may appear. Hence, we say, 

 that crossing produces a tendency to reversion or atavism.&quot; 



In crossing and grading up, always use a thoroughbred male, and the purer the blood of 

 the female, the better. A thoroughbred male upon low-bred animals always produces good 

 results, but a low-bred or grade male upon any kind of stock whatever, will result in disap 

 pointment. Therefore never use a male grade in breeding, no matter how fine an animal 

 he may be to look at, for he will not transmit his good qualities with any degree of certainty, 

 but will be very likely to transmit the undesirable qualities of his ancestors. The rule for 



