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Impressions in Sand, Etc

tioned liquid); if the part is only small, it will | paper will be in the least affected by this process, then rise quickly, and appear as if repainted.

New Mode of Preserving Impressions in Sand, etc.

A sheet of thin iron-plate was placed over the marks made, and supported by an iron stand, at a distance of about 1½ inches from the surface of the ground; a quantity of lighted charcoal was then placed on the iron plate, which soon became red hot, and of course heated the spot over which it was placed. When the latter was raised to 100° Centigrade (212º Fahr.) the fire, together with the plate, was removed, and a quantity of finelydivided stearic acid was strewed over the impression by means of a sieve. The powder used was that of a common stearine candle, dissolved by heat in alcohol, and then thrown into a large quantity of cold water, when the stearine falls to the bottom in the form of a fine precipitate. This powder is so light and impalpable, that it is said it might be sifted over an impression in the dust of a common road, without, in the slightest degree, interfering with the faintest mark. The instant it touched the heated surface of the ground in question it melted, and, as it were, sealed the whole of the loose atoms into one compact mass. When a sufficient quantity of the stearine had been applied, the place was left until it had become completely cold; the surrounding earth was then dug out carefully at some little distance from the edges of the impression, and the portion containing this latter was lifted up in one entire block, and laid on a cloth several times doubled, the edges of which were raised up so as to form a kind of border, or rather framing, into which, and against the sides of the sandy earth containing the impression, plaster of Paris was poured; and when the latter was set, the whole could be handled without danger, and was firm enough to bear packing and carriage to any distance. It is evident, therefore, that if necessary it might also be used as a mould, from which casts in plaster could be obtained. The value of such a process, as an aid in criminal cases, is too self-evident to require demonstration; the production of the tell-tale impressions in a court of justice, where every mark can be conveniently exhibited and compared with the object by which it was produced, may be equally useful in the proof of guilt and of innocence, and it would be strange, indeed, if a use for such a process be not discovered in matters of scientific or practical interest.

To make Writing Indelible.

The following simple process will make leadpencil writing or drawing as indelible as if done with ink. Lay the writing in a shallow dish, and pour skimmed milk upon it. Any spots not wet at first may have the milk placed upon them lightly with a feather. When the paper is all wet over with the milk take it up and let the milk drain off, and whip off with the feather the drops which collect on the lower edge. Dry it carefully, and it will be found to be perfectly indelible. It cannot be removed even with India-rubber. It is an old recipe and a good one.

To render Paper Fire-proof.

Whether the paper be plain, written, printed on, or even marbled, stained, or painted for hangings, dip it in a strong solution of alum-water, and then thoroughly dry it. In this state it will be fireproof. This will be readily known by holding a slip thus prepared over a candle. Some paper requires to imbibe more of the solution than by a single immersion, in which case the dipping and drying must be repeated until it becomes fully saturated. Neither the color nor quality of the but, on the contrary, will be improved.

A Composition to render Wood Fire-proof.

Glass made by heating sand with twice its weight of soda-ash or pearlash is soluble in boiling water, when finely powdered. Applied with a brush, it renders woodwork fire-proof, and when once dry is not affected by cold water.

To Render Dresses Incombustible.

Take of a solution of tungstate of soda, of a specific gravity 1-14, 100 parts; phosphate of soda, 3 parts. The articles are dipped in the solution, and allowed to dry before ironing. This solution keeps well, and is used in the Royal laundry.

How to Act when the Clothes take Fire.

Three persons out of 4 would rush right up to the burning individual, and begin to paw with their hands without any definite aim. It is useless to tell the victim to do this or that, or call for water. In fact, it is generally best to say not a word, but seize a blanket from a bed, or a cloak, or any woollen fabric - if none is at hand, take any woollen material - hold the corners as far apart as you can, stretch them out higher than your head, and, running boldly to the person, make a motion of clasping in the arms, most about the shoulders. This instantly smothers the fire, and saves the face. The next instant throw the unfortunate person on the floor. This is an additional safety to the face and breath, and any remnant of flame can be put out more leisurely. The next instant, immerse the burnt part in cold water, and all pain will cease with the rapidity of lightning. Next, get some common flour, remove from the water, and cover the burnt parts with an inch thickness of flour, if possible; put the patient to bed, and do all that is possible to soothe until the physician arrives. Let the flour remain until it falls off itself, when a beautiful new skin will be found. Unless the burns are deep, no other application is needed. The dry flour for burns is the most admirable remedy ever proposed, and the information ought to be imparted to all. The principle of its action is that, like the water, it causes instant and perfect relief from pain, by totally excluding the air from the injured parts. Spanish whiting and cold water, of a mushy consistency, are preferred by some. Dredge on the flour until no more will stick, and cover with cotton batting.

To Bleach Sponges.

Wash in hot dilute soda lye; then immerse in dilute muriatic acid, 1 part to 10 of water, until all gritty particles are removed, and no morė gas arises; then immerse in a second bath of dilute muriatic acid, containing 3 per cent. of hyposulphite of soda, for 48 hours. To take out Mildew.

Wet the linen where spotted in Labarraque's Solution (solution of chlorinated soda), or solution of chloride of lime (bleaching salt), or chlorine water; it will immediately disappear. Wash out at once with warm water. This is a better plan than that given in p. 314. Fruit and wine stains of all kinds may be removed in the same manner.

Simple Mode of Purifying Water.

A tablespoonful of pulverized alum sprinkled into a hogshead of water (the water stirred at the same time) will, after a few hours, by precipitating to the bottom the impure particles, so purify it that it will be found to possess nearly all the freshness and clearness of the finest spring-water.

A pailful, containing 4 gallons, may be purified by a single teaspoonful of the alum.