Of all the means of expression, photography is the only one that fixes forever the precise and transitory instant. We photographers deal in things that are continually vanishing, and when they have vanished, there is no contrivance on earth that can make them come back again. We cannot develop and print a memory. The writer has time to reflect. He can accept and reject, accept again; and before committing his thoughts to paper he is able to tie the several relevant elements together. There is also a period when his brain "forgets," and his subconscious works on classifying his thoughts. But for photographers, what has gone is gone forever.