CHEMISTRY. 



219 





sists of India rubber 7 parts, sulphur 2, phos- 

 phate of lime 2J, and phosphate of soda 2 parts. 

 The object of the invention is to form a com- 

 pound which will represent the natural bone, 

 and also resist the action of the acids of the 

 mouth and stomach. This compound is in the 

 plastic state moulded, and then hardened, in 

 the usual way, and after \vard polished. It is 

 then placed in an electro-galvanic bath, and a 

 thick coating of pure gold is deposited upon it. 



Guano Polishing Powder. A patent has 

 been solicited by Mr. W. Clark, of London, for 

 a new polishing material for steel and other 

 metals, as well as glass, composed of the ex- 

 tract of guano 100 parts, fine tripoli 25 parts, 

 common sea salt 10 parts, and wheat flour 12 

 parts. These substances being mixed and dried, 

 the powder formed is ready for use, save that 

 at the time of applying it is to be wet up with 

 dilute alcohol. 



Cement for Rooms. M. Sorel has discovered 

 that a compound which he terms oxy-cbloride 

 of zinc possesses advantages, as a coating for 

 the walls of rooms, over paint or plaster of 

 Paris. A coat of oxide of zinc mixed with size, 

 and made up like a wash, is first laid on the 

 wall, ceiling, or wainscot ; and over that a 

 coating of chloride of zinc, prepared in the 

 same manner as the first wash, is applied. The 

 oxide and chloride effect immediately a sort of 

 combination, forming a cement, smooth and 

 polished as glass, and possessing the advan- 

 tages of oil paint, without its disagreeable odor. 



Xeif System of B)ttlin<j Liquids. For bot- 

 tling beer, wine, cider, and other fermentable 

 and perishable liquids, one general method has 

 been in use from time immemorial ; the bottling 

 of milk, and the canning of eggs sa as to secure 

 their preservation, are still desiderata. Even 

 in the processes of bottling, or of canning fruits, 

 meats, etc., and hermetically sealing, a little air 

 must usually be left within, so that this by its 

 variations of volume under diiferent pressures 

 on it, may allow of the changes in the way of 

 contraction or expansion of the soft or liquid 

 contents, without risk of breakage of the ves- 

 sels either from without or within. But this 

 small quantity of air can suffice to set up fer- 

 mentation or decay. Mr. Henry Dircks has 

 proposed as a remedy against this evil a pre- 

 paratory filling of the bottles with nitrogen, 

 carbonic acid, or other innocuous gas, having 

 in itself no power to induce change in the 

 materials to be preserved, and which first serv- 

 ing like a filling with airless water to expel 

 the detrimental oxygen of the atmosphere, may 

 still remain in the small and needful quantity 

 within the bottles or cans, to protect them 

 during changes of volume of their contents. 

 The gases named are quite harmless to the 

 articles and to the health ; while the addition 

 in case of delicate old wines might be of great 

 service. The filling of the vessels with such 

 gases is easily effected on a large scale; 

 methods for the purpose will readily occur to 

 those conversant with like subjects one such is 



described in the " Athenamm," Jan. 1863. The 

 writer supposes that by a method such as there 

 indicated even fresh eggs, broken into cans con- 

 taining nitrogen gas. and sealed in such an at- 

 mosphere, may be kept without change. Any 

 shrinkage with the materials of any sort to be 

 preserved, either from escape of juices, or cool- 

 ing, could be replaced by the proper gas before 

 sealing. 



3~eic Process of Making Vinegar. Pasteur 

 has been investigating the property of myco- 

 derms, especially of those of wine and vinegar 

 the latter the mycoderma aceli, or micro- 

 scopic plant of mother of vinegar (Jleur du 

 finaigre) in virtue of which they act as con- 

 veyers of oxygen from the air into various mix- 

 tures of organic substances, and lead to oxida- 

 tion of the latter, often with a surprising rapid- 

 ity. He turns the new property to account in 

 a method for the manufacture of vinegar. The 

 method of vinegar making commonly adopted 

 in Europe with wines, and known as the Or- 

 leans process, has the disadvantage of producing 

 multitudes of vinegar eels (anguillulce aceti) 

 while the German method, of trickling the 

 liquid to be acetified over beech shavings is not 

 applicable to wine nor to beer in its natural 

 state, and produces an inferior article, lacking 

 the aroma of the original liquid. Pasteur sows 

 the dried and crumbled mass of mycoderms on 

 the surface of a liquid consisting of ordinary 

 water having in it .02 of its volume of alcohol, 

 and .01 of acetic acid from a previous operation: 

 to this he adds about T5 4oTT P art f alkaline and 

 earthy phosphates. The plant rapidly develops, 

 filling the whole liquid, and meanwhile the al- 

 cohol is acidified. When about half the origi- 

 nal alcohol is transformed, more alcohol, or 

 wine, or strong beer is added day by day. in 

 small quantities, until the liquid has about the 

 commercial strength. When the action of the 

 plant begins to be exhausted, it is left to com- 

 plete the acetification of the alcohol already in- 

 troduced : it is finally separated from the liquid, 

 and washed, yielding an acid and azotized liquid 

 capable of further use ; and the process is then 

 repeated with a fresh body of alcoholized liquid. 

 If at any time the plant wants a due supply of 

 alcohol, it will transform the vinegar to water 

 and carbonic acid ; and the like result will fol- 

 low if its growth is too rapid. Vessels about 

 40 inches square, and holding 10 to 20 gallons, 

 yield at the rate of a gallon or more of vinegar 

 a day. These may preferably be shallow wood- 

 en vessels, like the coolers used in brewing; 

 and gutta percha tubes made to run along the 

 bottoms of these, and perforated with small 

 holes along their course, may admit the alcohol 

 without disturbing the fungous film over the 

 surface. The phosphates are required as min- 

 eral food for the mycoderms ; the most suitable 

 are those of potash, magnesia, and ammonia. 

 The new process is not only suited to all the 

 liquids named, but besides, the presence in it 

 of the film of plants over the surface of the 

 liquid, by consuming (as it is introduced) the 



