(9) An imitation of Chinese gold lacquer may be prepared by melting 2 parts copal and 1 shellac until thoroughly mixed, and * adding 2 parts hot boiled oil. Then remove from the fire and gradually add 10 parts oil of turpentine. To colour, add gum gutta for yellow and dragon's-blood for red, dissolved in turpentine.
(10) Substitute For Gold Bronze
According to the experiments of Dr. B. W. Gerland, metavanadic acid may be used in the preparation of a substitute for genuine gold bronze. If a solution of sulphate of copper and sal ammoniac is mixed with vanadiate of ammonia and cautiously heated, there is obtained a compound of a splendid gold colour, which is deposited from the liquid in the form of gold-coloured spangles. These readily admit of being ground up with gum and varnishes, cover well, do not change on exposure to the air, and are in every respect equal to gold bronze. Iron and Steel Lacquers. -
(ft) A new preservative of iron and steel has been found in a modification of the well-known Japanese gum lacquer. After many experiments, the preparation has been finally adopted for the imperial Japanese navy. There is a certain difference between the compounds prepared for painting iron and steel and the ordinary lacquer employed for wood, but its principal element is still the gum lacquer. The inventor of the new composition had great difficulty in conquering the tendency of this material to get very hard and then to crack, but, according to the reports, he has succeeded at last. Experience has shown that a ship protected with this variety of lacquer has been able to keep afloat in tropical seas for 3 years - going into dry dock only once instead of 6 times during that time, as usual. A ship of the Russian Pacific squadron has tried the new coating, and the result has been very satisfactory. It is consequently thought that at last a toleraby perfect anti-corrosive coating for iron and steel structures has been discovered, which may render substantial service in the perservation of all descriptions of erections in these materials. The first cost of the preparation is rather high, but it is claimed that the excess of cost is more than compensated by the protection obtained.
For ship use it is also asserted that great advantage accrues from the high polish which this lacquer retains while the coating remains perfect, but, on the other hand, fears are expressed that the supply of gum lacquer will be unequal to the demand, if the requirements for these engineering purposes are added to the regular consumption of the article for ornamental joinery and cabinet work. (Sci. Am.)