323. The addition of clouds to a landscape cannot be too highly valued, but, alas! photography is too often unable to secure them with the average ment, perfect and complete gradations of tone, leading from deep shadow up to pure white in the sunshine, can be caught, provided both collodion and developer are in harmonious working order. - S. R. Stoddard.

323. All clouds can be photographed, from the lowering rain - cloud up to the sunny regions of the cirrus, those multitudinous and apparently motionless lines of delicate vapor with which the blue of the open sky is commonly streaked and speckled after some days of tine weather; but those most strongly marked in outline, and having the most favorable contrast of light and shade, are the easiest to secure on the plate prepared by the ordinarily used collodion process. The collodion should be very ripe, that is, it should have been iodized for many months, or, if newly iodized collodion only is obtainable, sufficient tincture of iodine should be added to it to make it a golden sherry color. The iron developer should be weak; about eight or ten grains to the ounce of water would be a suitable strength, with a corresponding amount of acetic acid and alcohol. The plate should be new, and very clean. Spots and stains are fatal to skies.

Any lens will do, but if a portrait or any quick one is employed, it should be stopped down. The difficulty in taking skies is to avoid excess of light, and to expose quick enough to prevent the plate fogging all over. The method of proceeding is as follows. Prepare and excite the plate in the usual manner. Expose, for a bright sky, as small a frac tion of a second as you can manage with the ordinary cap of the lens. Carry the slide to the dark-room, and develop. It is in the developing that the most judgment is required. In a matter so delicate as the guessed exposure of a fraction of a second, in which one ex. posure may be double that of another without the difference being noticed, a great deafe must be regulated in the development. Remember that the darkest parts of the clouds should be represented by bare glass in the negative, therefore, after the developer has been thrown on, and the high-lights and succeeding gradations, almost down to the darkest, have come out, pour a flood of water over the plate, and wash thoroughly. The negative must now be treated with a solution of iodine in iodide of potassium and water, made thus water, ten ounces; iodide of potassium, five grains; tincture of iodine, sufficient to produce a pale sherry color. This is poured over the plate, and washed off again. The intensification must now be commenced with pyrogallic acid, and will be found, if the clouds are delicate or feebly lighted, to be an operation requiring much patience. When the pyro becomes discolored, it should be washed off, and another dose of the iodine applied, after which fresh pyro again, and so on alternately until the requisite intensity is attained. - H. P. Robinson.

It is generally known by photographers that there are different methods of producing cloud effects by which satisfactory results may be obtained. Negatives taken from natural subject. By reference to the model picture, their value will be seen.

They may be secured seperately and printed in oftentimes, with admira-ble effect. As a usual thing, they are too rapidly moving to be secured with any detail, for while the foreground was being exposed, they would be over - timed and entirety Lost Sometimes, however, this is not so.

They must be treated much as children have to be in portraiture, and token when they are in quiet humor. Reflections in water are always attractive in a new. The water should be perfectly still, and the light brilliant. The finest reflection! occur when the atmosphere is foggy, but clouds, if tastefully selected and printed with care, add greatly to the picturesque and artistic finish of landscape pictures. It may happen at times, that out of a whole hatch of cloud negatives there is not one suitable for a particular picture which has to be completed. I have for some years past practised a method of producing cloud effects which has with me proved very successful, yielding proofs of a most delicate and refined character, giving great relief, yet in which there is nothing harsh to attract the eye from the subject, being very softly blended, and producing a most charming effect in the landscape picture. Procure a sheet of finely - ground glass the size of the negative, and, having previously printed a rough copy of the landscape, place it under the ground-glass laid upon a table, with the rough side of the glass upwards. It will then be observed that the picture is quite visible, thus offering every opportunity of arranging the clouds in any shape or form so as to harmonize with the subject. Now proceed to lay in the clouds with finely-ground black-lead powder, with the aid of a small sable brush, rubbing in those parts requiring to be most opaque with a small piece of India-rubber, afterwards tracing around the upper edges of cloud-masses with a lead-pencil, and gradually softening off the lower portions with the rubber. Take particular care to keep the whole nearly transparent. A little skill combined with taste is necessary to accomplish this with neatness, but it will be found after a little experience that some most excellent resemblances of clouds can be produced. It is advisable to make the sky portion of the negative quite opaque, so that the prints will remain perfectly white in the protected parts, which are to be printed under the cloud-glass. The easiest and quickest way to accomplish this is by blocking out upon the reverse side with black varnish, tracing within half an inch of the outline of the landscape, and then soften off the edges with a little gamboge (also upon the varnish side, if necessary). Should any parts of the picture print too dark, such as the foliage of leaves, they may be remedied by working in the details with a soft lead-pencil upon the varnished side. After printing from the negative in the usual way, place the print under the cloud-glass in an ordinary printing-frame, and printed under aired sunlight (previous to exposure). The frame should be covered with a folded sheet of yellow paper, and placed quite stationary; then, slowly drawing the paper from the top of the frame, exposing the sky portion to the light (care should be taken to go hut very little below the outline of the landscape), and then slowly closing it again. This may be repeated several times, and usually takes from two to three minutes, so as to print according to the depth required, which will depend upon judgment and taste. Good results may also be obtained by printing in the shade, and reversing the cloud-glass, so placing the rough side of cloud-glass next to the print. - Alonzo Ferrari.