We will enumerate the following colors in the order of their resistance, so to speak: 

No. 1.  White.  This color, theoretically a combination of red, green and violet will be found the hardest to eliminate, as the shade desired will have to be worked in, so to speak, and it will take several generations before a seal brindle with perfect markings that can be depended upon to always reproduce itself can be obtained.  Starting with a white bitch (always remember that the shades desired must be possessed by the dog), we breed her always to a golden brindle dog.  The bitches (those most resembling the sire in color being selected) from these two are mated to a dark mahogany brindle dog, and the females from this last union are mated to a dark seal brindle dog.  It will readily be observed that we have bred into the white color, golden, mahogany and seal brindle and this admixture of color will give practically over ninety per cent. of desirable brindles.  Always see that the sires used are perfectly marked, from ancestry possessing the same correct markings.  This is absolutely imperative, where the stock to be improved is worked upon is white.

No. 2.  Black.  This color is the opposite of white, inasmuch as there is an excess of pigment, which in this case will have to be worked out.  Breed the black bitch to a red brindle dog (with the same conditions regarding his ancestry).  The females from these matings bred always to a dark mahogany brindle dog.  The females from the last matings breed to a medium seal brindle dog with a very glossy coat, and the result of these last matings will be good seal brindles.  If any bitches should occasionally come black, breed always to a golden brindle dog.  No other shade will do the trick.

No. 3.  Gray brindle.  This is practically a dead color, but easy to work out.  Breed first to a golden brindle dog.  The females from this union breed to a rich mahogany brindle, and the bitches from this last litter breed to a seal brindle dog.

No. 4.  Buckskin.  Breed bitch to golden brindle dog; the females from this union to a red brindle dog (if unobtainable, use mahogany brindle dog, but this is not so effective), and the females from last union breed to a seal brindle dog.

No. 5.  Liver.  This is a great deal like the last, but a little harder to manipulate.  Breed first to a golden brindle dog.  The females from this union breed to a seal brindle.  The bitches from this union breed to mahogany brindle dog with black bars running through the coat, and the females from last mating breed to seal brindles.

No. 6.  Mouse color.  Use same process as for gray brindles.

No. 7.  Yellow.  A very undesirable shade, but easy to eliminate.  Breed to mahogany brindle dog as dark as can be obtained, and bitches from this mating breed to a seal brindle dog.

No. 8.  Steel and tiger brindles I class together, as the process is the same and results are easy.  Breed first to a red brindle dog; bitches from this union to a dark mahogany brindle, and then use seal brindle dog on bitch from last mating.