206 ANNUAL OF SCIENTIFIC DISCOVERY. 



can dispense with the use of acetic acid and bromine, and will 

 shortly be aide to brinij^ into the traile a superior articU^ nianutac- 

 tured by a method different from that already described by them. 

 — AIo. ScL 



NEW DTE FROM MADDER. 



Prof. Rochleder, of Pra<^ue, has found that, when madder is 

 treated with dikite mineral acids, it jields, beside alizarine and 

 pur))nrine, a small quantity of a third tinctorial substtmce, which 

 in alkaline solution lias a g;reat similarity to chrysophanic acid in 

 alkaline solution; acids precipitate it from this solution in the 

 amorphous, tiocculent state, the precipitate being of a pale yellow 

 color. This substance is soluble in alcohol and acetic acid, from 

 which solutions it is obtained by evaporation in orange-yellow 

 colored crystals. Its aqueous solution, mixed with acetic acid 

 and brought to the boiling point, imparts to silk and wool a 

 beautiful and durable golden-yellow color. — Cosmos. 



A NEW COLORING MATTER. 



The discovery of fuchsine and other colors derived from ani- 

 line first caused the existence of very rich sources of coloring mat- 

 ters to be predicted in mineral oils and hydrocarbons in general. 

 Therefore, since that period, chemists have devoted themselves to 

 laborious researches in the same direction, in order to find new 

 products for use in dyeing. The method which M, Clavel has 

 adopted was suggested by the study of the circumstances, wiiich 

 have since been explained, regarding the formation of fuchsine. 

 It is now known that commercial aniline is a mixture of aniline 

 and toluidine ; and M. Hofmann has proved that it is a mixture of 

 these two bases which produces the brilliant color, (juided by 

 an examination of these facts, M. Clavel has not sought in naph- 

 thylamine for a coloring matter by itself, but for one likely to 

 produce the color, by a mixture with another base like naphthy- 

 lamine, from which it has been derived, or with any other isomeric ' 

 substance. The new colorino^ matter, then, is obtaiiuul bv the 

 direct oxidation of a product isomeric with naphthylamine and 

 mixing the products of higher distillation with the naphthylamine. 



The mode of operation is as follows: The naphthaline is 

 first treated with nitric acid of 1.33°, and the resulting nitro- 

 naphthaline is washed, and reduced either l)y iron and acetic acid, 

 or by zinc and hydrochloric acid, or by other appropriate re- 

 agents. The distillation is then proceeded with. There comes 

 over at first naphthylamine, and then at a higher temperature a 

 second body discovered by M. Clavel. 



This second product is treated at 120° with 50 per cent, of veiy 

 dry nitrate of mercury, and subsequently left in contact with its 

 own bulk of naphthylamine for about a quarter of an hour; the 

 mixture is then treate<l with boiling water containing a vegetable 

 acid, by which the coloi ing matter is dissolved. After filtration 



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