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December 11, 1863.] THE PHOTOGRAPHIC NEWS. 595 have acquired of the texture of photographic proofs ;—it is that the metallic body which forms the picture is dissemi nated and not continuous ; from this, there results centres of action, which are so much the more numerous as the effect of the light has been more intense ; but they never touch each other, except, perhaps, in an over-exposed or solarized proof. Upon the discovery of the Daguerreotype, chemists of eminence analyzed the silver pictures, and they concluded, as 1 have before stated, that Daguerrian pictures were en tirely formed of little isolated deposits ; and when I took up the practice of this wonderful process, I verified this fact myself, by the microscope upon prodigiously sharp pictures obtained with a diaphragm as small as a pin-hole. So then, it is the same with proofs on collodion : the particles of re duced silver are isolated from each other, and if by chance some are in contact, there are hero and there some branches starting from a centre around which they radiate. But as every proof is formed of multiplied alternations of light and shade, or what is the same thing, of regions where the silver is thinly spread, but, as a whole, always disseminated with vacant intervals reserved, however small they may be between the metallic particles: it results that the electricity of the pile cannot circulate from one to another, as that requires perfect metallic contact. Such, in fact, is the essential condition for the electricity of ordinary piles to transmit its action to the greatest dis tances ; the most powerful tension cannot overcome this con dition, which is certainly not met in collodion proofs. But we know two different methods of producing electricity, each of which has its special attraction—static electricity and dynamic electricity: the one produced by friction, the other by chemical action ; electricity of tension and electricity of quantity; electricity of induction and direct electricity. That is the latest definition of it. To arrive at the result, we shall say that there is an elec tricity which is propagated only by a continuous metallic contact, and an electricity which crosses the metallic discon tinuities, when its force is in proportion with the interval which makes the discontinuity. Thus the powerful battery capable of the brilliant well-known electric light can enter into operation only by the effectual contact of its poles; but by interposing the Ruhmkof coil, the spark becomes apt to cross distances of 50 centimetres (20 inches) to one thousandth of a millimetre, according to the power of the battery ; like the lightning, which, by means of its vast appa ratus, darts its bolts, which are evolved in serpentine form, exactly like those produced by the Ruhmkoff coil. There fore, what must be done to intensify collodion negatives by the pile ? We must combine its elements with a Ruhmkoff coil, and then the electricity will not fail to produce its effect over the entire surface of the proof, as though conti nuity existed. Ill speaking of intensifying pictures by the pile, I do not wish to say that we must substitute this new method of ordinary strengthening a picture for the usual practice ; but there is a very interesting case which demands its aid. I speak of instantaneous pictures, which require only the tenth of a second’s exposure for small size ; and it will be a very great advantage if we can, by intensifying with the pile, ope rate with half the present exposure only; for it is admitted that the most fugitive proof is perfect at first, and that it arrives at the desired intensity only by a development wdiich is really an intensifying. This is so true, that I have often obtained positive proofs upon glass with sulphate of iron, which, although scarcely visible to the ordinary eye, appear under the microscope models of ideal perfection. If I do not deceive myself, these proofs were susceptible of being strengthened by the pile, according to the method I have suggested to physicists, who have suitable apparatus at their disposal, and can bring this delicate operation to a good issue, which requires a piece of good leaf to be placed on the edge of the glass plate, so as to connect with the picture, and the application of a small piece of silver upon the gold leaf.— La Isumiire. CHILDREN'S PICTURES* I am an amateur in photography in a small way, and read the Journal, of course. Many a difficulty have I mastered by its aid. But now help is wanted, not for me alone, but for a suffering profession. Hear the case. Convenient to me is the thriving town of B, which boasts of three photographers. Good fellows, all of them; know a thing or two, and can take a hint or a picture in reasonable time. When in town, I always look in upon them, to chat a little on art matters, and compare our work. A few days since I walked in friend A’s pleasant rooms. A is a. spruce young laddie, very civil and obliging, and always balmy as a May morning to his lady customers. I found him in his dark room, rather nervous. “Fact is, Sam, I have about a dozen babies, more or less, to take this morning;” and an occasional squall from the reception room confirmed his words. A urged me to stay a little while, and I stayed. Baby No. 1 came in accompanied by pa, who carried the baby ; ma, who did the baby talk, and a plenty of it; and two small sisters, who capered and crowed to amuse the dar ling. Excepting that the baby’s head would not keep up any way, and that he would suck his thumb, or cried if that favour was denied him, he wasn’t a bad sitter. But these trifling drawbacks consumed an hour or so, and baby was only caught at last when in the act of dropping to sleep, his head held up by hand, and the countenance decidedly puttyish. Ma was dissatisfied, but pa was in a hurry, and A strained his conscience, affirming that the picture was very good. After some vain attempts to beat down prices, the party left, making room for an interesting pair of twins, whereon I fled despairingly. Friend B is a man of few words, and those biief, like Pat’s owl, “ he kapes up a dale a’ thinkin.’’ I found him trying to take a family group, consisting of a mother, a spoiled three year old boy, and a six months’ baby. My friend’s counte nance was an artistic study, and expressed a variety of con tending emotions, prominent among which I could read a desire to shake the spoiled boy, and free his mind to his mother, while a desire to get a customer was fighting hard with his honest indignation. After waiting for half an hour in vain, I left him in his dark closet preparing his ninth plate, and growling something about the malignant abuse of Herod for the slaughter of the innocents. Friend C is a batchelor of the most straitest sect. Babies and baby talk are to him an abomination. He is in dress, movements, and conversation, a model of sedate propriety. Judge of my surprise, when, on entering his room, and peering cautiously around the screen, I beheld him shaking a child’s rattle with might and main, and trying at the same time, to whistle " Pop goes the weasel,” with variations. At last off went the cover, but the whistle and rattle ceased, and the baby threw back its head and bellowed ; mother hush-a- byed, and 0, with a look of desperate resignation, prepared another plate, and resumed his musical labours; but baby refused to attend, and, as I fancied, winked precociously out of his right eye, as if he liked to see the fun. “ Can’t you try something else, Mr. C,” said the anxious parent, and C, after profound meditation, rushed into the closet, extempo rised a drum out of a gutta percha 4-4 bath, and by energetic thumping, succeeded in fixing the infant’s attention. Cau tiously he uncovered, and, warned by previous experience, he redoubled his musical exertions, accompanying them with a kind of war whoop and scalp dance, which would have done credit to any of Barnum’s Winnebagoes. The result, I am happy to say, was a very faint picture of a very much astonished urchin with eyes like saucers; but there was a picture, and C sat down exhausted. I offered some ironical congratulations upon his success, but he was too deeply touched. More in sorrow than in anger, he waived the sub ject, solemnly averring that such labours as these just re- * The American Journal of Photography,