CHEMICAL SCIENCE. 277 



liquid, in surmounting these difficulties, and rendering the application of 

 this new paint easy. 



The liquid which in this paint replaces oil, essence of turpentine, and the 

 other liquids and excipients used in ordinary painting, is an aqueous solution 

 of chloride of zinc, in which I have dissolved an alkaline tartrate. These 

 salts possess in the highest degree the property of retarding the thickening 

 of the new paint before being used. I add to the liquid, to give tenacity to 

 the paint, gelatine or fecula which I have caused to pass into the state of 

 starch by heating the liquid. It must not be heated so much as to transform 

 the feciila into dextrine or glucose. 



To form the new paint, whatever the color may be, I use the above liquid 

 and a powder which should be in great part oxide of zinc. For colored 

 paints I use the same powder plus the coloring matters. The colors usually 

 employed in ordinary painting may be employed. 



The new paint possesses the following properties : 1st. It is not necessary 

 to grind it; the powder only requires to be diluted with the liquid, and the 

 paint is used in the ordinary manner. 2d. It is more beautiful and more 

 solid than oil paint ; it covers better, and is not rendered black by sulphurous 

 emanations, like paints of ceruse or other lead bases. 3d. It is absolutely 

 without odor, and dries very rapidly. We can apply a layer every two hours 

 in winter, and every hour in summer; which enables us to paint an apart- 

 ment in one day and inhabit it the same day, without being affected by the 

 odor of the paint. 4th. It resists moisture and water, even when boiling, 

 and may be washed with soap like oil paint. 5th. In consequence of the 

 chloride of zinc which it contains, the paint is eminently antiseptic, and fitted 

 to preserve wood from perishing. 6th. It possesses to a very high degree 

 the quality of diminishing the combustibility of wood, fabrics, and paper, 

 and of rendering these matters uninflammable. 7th. It is perfectly innocu- 

 ous both to those who prepare and those who use it. 



I have also the honor of placing before the Academy a new translucid 

 plastic matter, which is formed with the principal elements of the paint of 

 which I have just spoken, but in very different proportions. It is a combi- 

 nation of potato fecula and hydrated chloride of zinc, of a sufficient density 

 to swell the fecula without dissolving it. To modify the hardness of the 

 matter, and to render it more or less white or more or less opaque, certain 

 salts or powdered matters are added, such as oxide of zinc, sulphate of 

 baryta, etc. This plastic matter is prepared cold by moistening the fecula 

 and other matters with chloride of zinc. This new compound is easily 

 moulded, and solidifies in the mould like plaster. The objects thus obtained 

 are as translucid as horn, bone, or ivory; but to obtain this translucidness, 

 very little or none of the moist pulverulent substances must be introduced, 

 except sulphate of baryta. This salt, although insoluble, gives very little 

 opacity to the matter. This is not the case with oxide of zinc or carbonate 

 of lime. 



To keep the objects thus obtained from moisture, they are covered with 

 one or two layers of good varnish. 



Any color may be given to this new matter, and it may be obtained more 

 or less hard; it may even be obtained as supple as caoutchouc, but not 

 elastic. 



This new plastic compound may be used for moulding many objects of 

 art and ornament, and in the manufacture of many things requiring either 



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