pt, is neither to cross nor to breed from close affinities--except in
rare instances, and for some specific and clearly understood
purpose--but to _breed in the line_; that is, to select the breed or
race best adapted to fulfil the requirement demanded, whether it be for
the dairy, for labor, or for such combination of these as can be had
without too great a sacrifice of the principal requisite, and then to
procure a _pure-bred_ male of the kind determined upon, and breed him to
the females of the herd; and if these be not such as are calculated to
develop his qualities, endeavor by purchase or exchange to procure such
as will. Let the progeny of these be bred to another _pure-bred_ male of
the same breed, but as distantly related to the first as may be. Let
this plan be faithfully pursued, and, although we cannot, without the
intervention of well-bred females, procure stock purely of the kind
desired, yet in several generations--if proper care be given to the
selection of males, that each one be such as to retain and improve upon
the points gained by his predecessor--the stock, for most practical
purposes, will be as good as if thorough-bred. If this plan were
generally adopted, and a system of letting or exchanging males
established, the cost might be brought within the means of most persons,
and the advantages which would accrue would be almost beyond belief.

A brief summing-up of the foregoing principles may not be inappropriate
here.

The law of similarity teaches us to select animals for breeding which
possess the desired forms and qualities in the greatest perfection and
best combination.

Regard should be had, not only to the more obvious characteristics, but
also to such hereditary traits and tendencies as may be hidden from
cursory observation and demand careful and thorough investigation.

From the hereditary nature of all characteristics, whether good or bad,
we learn the importance of having all desirable qualities _thoroughly
inbred_; or, in other words, so firmly in each generation that the next
is warrantably certain to present nothing worse--that no ill results
follow from breeding back to some inferior ancestor--that all
undesirable traits or points be, so far as possible, _bred-out_.

So important is this consideration, that, in practice, it is decidedly
preferable to employ a male of ordinary external appearance--provided
his ancestry be all which is desired--rather than a grade, or
cross-bred