(1) Thoroughly clean the glass, then take some very weak isinglass size, and while warm float the glass where you intend the gold to be laid, with the size and a soft brush; then lay the gold on with a gilder's tip, previously drawing it over the hair of your head to cause the gold to adhere to it. Tilt the glass aside to allow the superfluous size to run away, then let it dry, and if it does not look sufficiently solid upon the face, give another layer of gold the same way. Where the black lines are to show, take a piece of pointed firewood, cut to the width the lines are needed, and with a straight - edge draw a line with the piece of wood, which, if made true and smooth, will take the gold off clean, and so square and sharpen up all the edges, lines, etc. When this is done, give a coat of Brunswick black thinned with a little turps, and the lines will show black, and it will preserve the gold. Try a small piece first, so as to get all in order.

(2) The proper flux is anhydrous borax; the real gilding is effected by the aid of heat. For this purpose a solution of gold in aqua regia (chloride of gold) is precipitated by potash or green vitriol - a finely - divided powder (brown) consisting of metallic gold. This is washed, dried, and rubbed up with the flux (anhydrous borax). Mix the same with oil of turpentine or gum - water; apply with a brush. When heated in the muffle, the volatile oil escapes; the gum consumed, the borax melts and firmly attaches the gold to the surface of the vessel.

(3) 2 gr. of isinglass; new rum, 2 parts; water, 3 parts. Put the water and the isinglass into a clean pan, and let them simmer over the fire for about an hour; add the rum when taken off the fire, then let it cool. Clean the glass, pour on the liquid, gild with camel's - hair tip, set the glass upon its edge; the liquid will run from beneath the gold, and in less than 20 minutes you will have a burnished plate. When dry, rub lightly with fine cotton; if there are any spots not gilded, gild them. Draw your design on paper, perforate your lines with a needle, put your paper next the gilded side, with the reading the wrong way, dust through the holes with a rag and whiting, lift off the paper, and you will find your design marked off. If you wish the letters left clear black, cut round the letters with yellow, paint all over but the letters, wash off the gold with water, then paint all over black. If you want the letters gold, paint the letters yellow, and wash off the surplus gold, then paint all over black.

(4) Prof. Schwarzenbach, of Berne, has recently devised the following method of gilding on glass: - Pure chloride of gold is dissolved in water. The solution is filtered and diluted until in 20 qt. water but 15 gr. gold are contained. It is then rendered alkaline by the addition of soda. In order to reduce the gold chloride, alcohol, saturated with marsh gas and diluted with its own volume of water, is used. The reaction which ensues results in the deposition of metallic gold and the neutralization of the hydrochloric acid by the soda. In practice, to gild a plate of glass, the object is first cleaned, and placed above a second plate slightly larger, a space of about 1/10 in. separating the two. Into this space the alkaline solution is poured, the reducing agent being added immediately before use. After 2 or 3 hours' repose, the gilding is solidly fixed, when the plate may be removed and washed.