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might be due tQ the action of the aniline color alone, are also due to a 

 certain extent to the arsenic it contains, as well as to the partial de- 

 composition of the meat which it often masks, but does not, by any means, 

 remove. This fraud may be easily detected by treating a sample of the 

 suspected meat with alcohol or ether; the fuchsin, if it be present, being 

 soluble, will be extracted, while the blood-coloring matter will remain 

 behind. The aniline red will appear, but, upon addition of a little acid, 

 it will be removed. Soda or potash will change the red to yellow, or 

 render the solution almost colorless. 



Urcdo, its chemical properties. — In certain localities this species of fun- 

 gus is very abundant, appearing upon the corn, increasing the grain to 

 a large oval bladder, which becomes filled with a brown or reddish pow- 

 der; the ear is sometimes entirely covered, thus increasing so much in 

 size and weight as to cause the peduncle by which it is supported to 

 bend. M. Harsten, who has examined it chemically, reports upon it as 

 'follows : 



The coloring-matter seems to be intimately incorporated in the material forming the cell- 

 Avalls, and cannot be extracted by any of the solvents generally used for this purpose, since 

 it fails to be taken up by ether, absolute alcohol, benzole, petroleum, chloroform, acetic acid,_ 

 or caustic potassa. This fungus, when heated dry at 100° C., is perfectly ordorless, but when 

 boiled with water it liberates an intense bituminous and very disagreeable odor. By con- 

 densation of these vapors a fetid liquid is obtained, in which,' after standing twenty-four 

 hours, small drops of a caniphorous material are formed, which, when examined with a 

 microscope, show a crystalline structure. The cell-walls show considerable resistance to 

 the action of acids. Warm sulphuric acid attacks them but slightly, producing sulphurous 

 acid ; acetic acid and boiling caustic potassa fail to produce a noticeable effect, but if it be 

 boiled with dilute sulphuric acid a strong odor of bees-wax is developed, a volatile acid and 

 an inflammable gas are liberated. A cold mixture of sulphuric and nitric acids in proportions 

 necessary to the production of pyroxylene renders the color of uredopale, without otherwise 

 changing its appearance. After being washed and dried it burns easily, without explosion. 

 Nitric acid causes it to swell, and then attacks it, producing a strong odor of bitter almonds ; 

 the cell-walls gradually disappear and the liquid contains oxalic and suberic acids, and a 

 very considerable quantity of fat. The weaker reagents seem to be incapable of extracting 

 the fat from the uredo, unless the cell-walls be first destroyed or modified by nitric acid, chlo- 

 rine, sulphuric acid, bichromate of potassa, &c. These substances cause it to yiel(^ its fat 

 to benzine. The odor of acroleine was not perceived in its decomposition. Glycerine is also 

 wanting. Boiling water extracts a small quantity of fixed matter partially precipitable by 

 acetate of lead. 



Tannic acid as a icood-preservatii'e. — M. Hatzfeld presented, at one of 

 the late meetings of the Academy of Sciences of Paris, a paper upon the 

 preservation of wood by means of tannic acid and protoxide of iron. 

 He urges that the tannic acid, combining with the albuminoids of the 

 wood, isable to form insoluble tannates, and thus remove in a great 

 measure the support of the vegetable and animal parasites, which are 

 so abundant; that the more durable woods are those containing the 

 greatest amount of tannic acid, and that this substance is therefore 

 the true natural preservative. Besides injecting tannic acid into the 

 softer woods for their preservation he proposes to harden them by 

 further treatment with protoxide of iron. This may be applied after the 

 tannic acid or in conjunction with it. The tannate of the protoxide of 

 iron being perfectly colorless, blackens upon exposure to the air, and 

 when injected into the wood, is deposited in the cells on account of this 

 transformation, thus increasing its density to a wonderful extent. 



