_Mr. Lyte's New Instantaneous Process._--I beg to communicate to you a new process in photography, which is by far the most rapid I believe yet discovered, and combines at the same time great stability. It has been the result of a great many experiments on my part, and even now I am hardly prepared to say that it is brought to its fullest perfection; but it suffices to say that it is sufficiently rapid to give pictures of the waves of the sea in motion with perfect sharpness, and ships sailing at ten knots an hour, and puttling up and down at the same time, and all with a landscape lens. By it also, and by the same lens, we may take instantaneous portraits. The process is as follows:--After the plate, prepared with the collodion and sensitised with the nitrate bath, as I have described in one of your former Numbers, is taken from the bath, I pour over it a solution composed as follows: 1. Take-- Nitrate of silver 200 grains. Distilled water 6 ounces. Iodide of silver, as much as will dissolve. Mix and filter. 2. Take-- Grape sugar or honey 8 ounces. Water 6 ounces. Alcohol 1 ounce. Mix, dissolve, and filter. And when required for use, mix equal parts of these solutions, and pour them over the plate. The plate is to be allowed to drain; and then, when placed in the frame, is ready for the camera, and is easily impressed as a deep negative by a Ross's landscape lens instantaneously. To develop, I use always the same agents as I have before specified. One or two cautions are to be observed in this process. First, the grape-sugar or honey must be quite pure, and free from any _strong_ acid re-action; and, secondly, these substances are much improved by a long exposure to the air, by which the oxidation of them is commenced, and the result made much more certain and effective. However, I find that the addition of the least possible quantity of nitric acid has the same effect; but nothing is so good as long exposure of the sugar or honey, so as to become completely candied before mixing. The sugar may as conveniently of course be mixed in the collodion as in the bath, but in that case the keeping properties are lost, as the plate is not thus kept longer moist than usual. If, however, the former process be used and well conducted, the plate when sensitised may be kept for four hours at least without injury. The grape sugar should be made with oxalic, and the acid removed by lime as usual, and not with sulphuric acid, as is often done; as in the latter case sulpho-saccharic acid is formed, which much injures the result.