MECHANICS AND USEFUL ARTS. 97 



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ZEIODELITE A NEW MINERAL PASTE. . 



The London Chemical News describes, under the above name, a new kind 

 of paste, discovered by Joseph Simon, which becomes as hard as stone, is 

 unchangeable by the air, and, being proof against the action of acids, may 

 replace lead and other substances for various uses. It is made by mixing 

 together nineteen pounds of sulphur and forty-two pounds of pulverized 

 stoneware and glass. The mixture is exposed to a gentle heat, which melts 

 the sulphur, and then the mass is stirred until it becomes thoroughly homo- 

 geneous, when it is run into suitable moulds and allowed to cool. This pre- 

 paration is proof against acids in general, whatever their degree of concen- 

 tration, and will last an indefinite time. It melts at about 120 Centigrade, 

 and may be reemployed without loss of any of its qualities, whenever it is 

 desirable to change the form of an apparatus, by melting at a gentle heat, 

 and operating as with asphalte. At 110 Centigrade it becomes as hard as 

 stone, and therefore preserves its solidity in boiling water. Slabs of zeiode- 

 lite may be joined by introducing between them some of the paste heated to 

 200 Centigrade, which will melt the edges of the slabs, and when the whole 

 becomes cold it will present one uniform piece. Chambers lined with zeio- 

 delite in place of lead, the inventor says, will enable manufacturers to pro- 

 duce acids free from nitrate and sulphate of lead. The cost will be only one- 

 fifth the price of lead. The compound is also said to be superior to hydraulic 

 lime for uniting stone and resisting the .action of water. 



PLASTIC COMPOSITIONS IN LIEU OF MARBLE. 



A Mr. Brooman, of London, has invented a composition, to be used for 

 building and decorating purposes in lieu of marble, which he calls " simili- 

 marble." A communication in the London Engineer describes the process 

 of manufacture as follows: 



To manufacture similimarble intended to remain white, take sulphate 

 of potass about fourteen ounces; river water, sixteen quarts; gum arabic, 

 two pounds ; purified cement, twenty pounds ; marble or alabaster powder 

 or dust, twenty pounds ; and treat as follows : First mixture Dissolve 

 over a slow fire, stirring all the time, fourteen ounces of sulphate of potass 

 in sixteen quarts of Avater; after fusion, dissolve two pounds of gum arabic. 

 Second mfxture Stir together twenty pounds of purified cement, twenty 

 pounds of marble or alabaster dust, and five pounds of lime, slacked suffi- 

 ciently to cause it to crumble into powder. Pour into a mortar of marble, 

 porcelain, or other suitable material, a part of the first and a part of the 

 second mixture, and stir with a wooden or bone spatula until the ingredients 

 assume the state of thick paste; then beat with a pestle until the mass 

 becomes elastic, which Avill be ascertained by the composition not adhering 

 to the pestle. To make mouldings or castings, grease the mould, and apply 

 a first layer of about one-third of an inch in thickness of the composition 

 as aforesaid; this first layer is backed by another, formed by boiling, for 

 about three or four hours over a brisk fire, hemp, tow, or other filamentous 

 substances, cut small, in the " first mixture " of gum and sulphate of potass. 

 The product is mixed with the " second mixture" in a mortar, and well beaten 

 with a pestle until the filamentous parts are divided through the mass, and 

 the whole reduced to a paste. Thus a composition of great solidity and im- 

 permeability is produced, lighter than and taking an equal polish to marble, 

 and resisting the action of frost better than marble. 



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