546 ANNUAL RECORD OF SCIENCE AND INDUSTRY. 



IMPROVED DRAAVING-INK. 



The addition of one part of carbolic acid to eighty parts of 

 the fluid India ink, while it does not impair its fluidity, causes 

 it to dry raj^idly, even in heavy lines, so that they can be var- 

 nished over. The proper amount of carbolic acid to be used 

 in any case may be ascertained by adding, droj) by drop, the 

 ordinary apothecary's solution of it in alcohol, until varnish- 

 ing does not affect the definition of a test line by causing it 

 to run. The addition of too much carbolic acid is indicated, 

 by the transparency of the line and inability to draw fine lines, 

 a condition easily remedied, by the addition of more of the 

 fluid ink. 6 (7, N'ovemher 7, 1872, 448. 



POETABLE INK. 



Professor Bottger has lately recommended a new kind of 

 ink especially adapted for the purposes of travelers. In its 

 preparation some white blotting-paper is saturated wuth ani- 

 line black, and several sheets are placed together, so as to 

 form a thick joad. When wanted for use, a small piece is torn 

 oft' and moistened with a little water, the black liquid which 

 dissolves out making. a good writing-ink. A square inch of 

 the paper will give enough ink for a considerable amount of 

 writing, and a few pads Avould be sufticient for an exploring 

 pf^rty ; and as water can generally be obtained any w^here, 

 the necessary amount of ink will always be readily available. 

 18 A, March 14, 1873, 625. 



BLUE STAMPING-INK. 



An excellent blue stamping ink, according to Bottger, is 

 prepared by dissolving white glue in concentrated glycerine 

 at a slight heat, adding a sufticient quantity of Thenard blue, 

 and thickening the whole with enough finely powdered gum- 

 arabic to bring it to the proper consistency. 13 C, Sejytemher 

 19, 1872, 398. 



INERASIBLE WRITING-INK AND BLACK ANILINE VARNISH. 



An ink that is not affected by strong mineral acids nor al- 

 kalies, and at the same time Avill not corrode steel pens, may 

 be made by triturating 60 grains of aniline black with a 

 mixture of 60 drops of concentrated hydrochloric acid and 



