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.
Portrait Work, Over - Exposed. In slight overexposure of portraits, start the plate in half old and half fresh developer. This many times will sufficiently restrain the shadows. If this is not enough, you can immerse quickly the plate for only a second in a weak bromide solution of one dram ten per cent, solution of bromide to one-half-pint water. The longer you allow the plate to remain in the bromide bath, the more it will restrain. If the plate is over-exposed only a little more than you can control with the half old and half new developer, immerse the plate for a second in the bromide bath. If the plate is considerably over-timed, then allow it to remain longer in the bromide. You must be guided entirely by the appearance of the plate when in the first developer, as to how much to restrain it. You can restrain as little or as much as you require by this method.
256. In order to become familiar with the advantages of these methods of developing, make two over-timed exposures. Develop one plate in the normal developer; the other develop according to instructions for over-exposures. Make proofs from both plates, noting on backs of same developer used, and any other data that will aid you in your future developing. Save these proofs, filing in your proof file for future reference.