Before commencing to treat of the most correct methods to be observed in the breeding, it will be as well to mention the different varieties of sporting dogs, and also the various sub-genera of each species, of which every one who knows anything of the subject need not be informed; but as this work affects to be a Vade Mecum for sportsmen, young far more than old, it is as well to put before the young idea certain established rules, not to be violated with impunity, and without following which no kennel can be great or glorious. A run of luck may perhaps happen, to set at naught all well defined rules, but "breeding will tell" sooner or later; and, therefore, it behoves any person who prides himself on his kennel, to study well the qualities of his dog or bitch, his or her failings and good qualities, and so to cross with another kennel as to blend the two, and form one perfect dog. This is the great art in breeding, requiring great tact and judgment.