This section is from the book "The Dogs Of Great Britain, America, And Other Countries. Their Breeding, Training, and Management in Health and Disease", by John Henry Walsh (Stonehenge). Also available from Amazon: The Dogs Of Great Britain, America And Other Countries.
Although many of the breeds which have been enumerated in the preceding chapters were most probably the produce originally of crosses between distinct varieties, yet at present they are continued by breeding from a sire and dam of the same kind. But with those which we are now about to consider, there is constantly a necessity for having recourse to the original breeds. For instance, many breeds of the greyhound are known to be crossed with the bull, and the identical animal with which the cross first commenced is well ascertained, as in the case of Sir James Bos well's "Jason," Mr. Etwall's "Eurus," etc.; so also with the foxhound, though here the particular cross is not so well ascertained, but it is admitted to have taken place within the last century. Yet these are not called mongrels, and the breed, instead of being despised as such, is more highly prized than those of the pure strain which formed one side of the parent stock. The term mongrel may more properly be applied to those chance crosses which occur from accident or neglect, the bitch selecting her own mate, and being guided by caprice, without regard to the fitness of the match in reference to the progeny resulting.