This section is from the book "Complete Self-Instructing Library Of Practical Photography", by J. B. Schriever. Also available from Amazon: Complete Self-Instructing Library Of Practical Photography.
Introduction. Believing it essential that the photographer should be competent to manipulate any of the standard American brands of plates, it is advisable, therefore, that each brand be given careful trial. In order to obtain the very-best results one should work each plate under all conditions, and when trying one brand of plate do not attempt to work another until you have mastered the particular plate you are manipulating. After all the different brands have been worked, and you are quite familiar with their manipulation, then you can intelligently determine which is best suited for your particular work.
550. In order to supply the reader with still more valuable information regarding any particular standard American make of plates, we have had the different manufacturers prepare for us special instruction, which they have compiled from the information obtained from their numerous demonstrators, operating in all parts of the country. This special information covers the manipulation of all their different brands of plates, and is supplied under their respective headings, in the following chapters: -