We have hitherto chiefly considered the effects of crossing in giving
uniformity of character; we must now look to an opposite result. There can be
no doubt that crossing, with the aid of rigorous selection during several
generations, has been a potent means in modifying old races, and in forming
new ones. Lord Orford crossed his famous stud of greyhounds once with the
bulldog, in order to give them courage and perseverance. Certain pointers have
been crossed, as I hear from the Rev. W.D. Fox, with the foxhound, to give
them dash and speed. Certain strains of Dorking fowls have had a slight
infusion of Game blood; and I have known a great fancier who on a single
occasion crossed his turbit-pigeons with barbs, for the sake of gaining
greater breadth of beak.

In the foregoing cases breeds have been crossed once, for the sake of
modifying some particular character; but with most of the improved races of
the pig, which now breed true, there have been repeated crosses,--for
instance, the improved Essex owes its excellence to repeated crosses with the
Neapolitan, together probably with some infusion of Chinese blood. (15/22.
Richardson 'Pigs' 1847 pages 37, 42; S. Sidney's edition of 'Youatt on the
Pig' 1860 page 3.) So with our British sheep: almost all the races, except the
Southdown, have been largely crossed; "this, in fact, has been the history of
our principal breeds." (15/23. See Mr. W.C. Spooner's excellent paper on
Cross-Breeding 'Journal Royal Agricult. Soc.' volume 20 part 2: see also an
equally good article by Mr. Ch. Howard in 'Gardener's Chronicle' 1860 page
320.) To give an example, the "Oxfordshire Downs" now rank as an established
breed. (15/24. 'Gardener's Chronicle' 1857 pages 649, 652.) They were produced
about the year 1830 by crossing "Hampshire and in some instances Southdown
ewes with Cotswold rams:" now the Hampshire ram was itself produced by
repeated crosses between the native Hampshire sheep and Southdowns; and the
long-woolled Cotswold were improved by crosses with the Leicester, which