POPULAR SCIENCE BEYIEW. 
' 88 
denoting the decrease of specific gravity 0001461 for each degree Centi- 
grade. 
Improvements in Dyeing. — Several improved methods are described in 
No. 40 of “Reimanns Farber Zeitung.” This number contains receipts for 
a catechu brown on glazed calico ; an iron buff on stout cotton goods ; for a 
deep olive-green and a drap on wool ; a coal-black, a blue-black, and a deep 
corinth on plush ; also a black on cotton yarn, capable of bearing milling ; 
and a blue on shoddy, the cotton in which has been first destroyed by the 
vapour of hydrochloric acid, and the residue neutralised with chalk. In 
dyeing, also, a preparation is used, known as “ shoddy-carmide.” It is 
made by dissolving, in two pails of hot water — 12 lbs. of alum, 9 lbs. of 
indigo-carmine, and 3 lbs. of soluble aniline blue. 
Death of Professor Dr. F. Grace- Calvert, F.P.S. — The “Chemical News ” of 
October 31 records the death of this gentleman, whose contributions to 
chemistry have so frequently enriched its pages. Crace-Calvert spent the 
early years of his life in France. After his return to England he became 
Honorary Professor of Chemistry in the Royal Institution of Manchester, 
which position he continued to hold up to the time of his death. In 1850 
he was also Lecturer on Chemistry in the Pine Street Medical School, 
Manchester, an appointment which he does not seem to have held later than 
1855. In 1859 he was elected a Fellow of the Royal Society. He was also 
a Corresponding Member of the Academy of Sciences of Turin, Honorary 
Member of the Pharmaceutical Society of Paris, and Corresponding Member 
of the Industrial Society of Mulhouse. He died on the 24th of October, at 
the age of 54. “For many years,” says the editor of the “ Chemical News,” 
“ we enjoyed the pleasure of his friendship, and few can give more able testi- 
mony to his worth as a chemist, or his faithfulness as a friend.” 
Absorption and Spontaneous liquefaction of Gases by Charcoal . — In “ Les 
Mondes,” Oct. 9, is an important contribution by M. Melsens, who states that 
he has obtained wood charcoal absolutely pure, and possessed of such high 
absorptive power that it can concentrate in its pores its own weight of gas. 
When charcoal thus saturated with any of the more readily liquefiable gases, 
such as cyanogen or chlorine, is placed in a glass tube fitted with a neck bent 
at right angles and closed at one end, and heated to 100° by a current of 
steam, the gas escapes, and, compressing itself in the closed end of the tube, 
passes at once to the liquid state. 
How to print Aniline Colours on Calico. — First, a solution of gelatin is 
prepared, containing about 50 gnus, to the litre of water. Solution of 
bichromate is added drop by drop till a straw-colour is produced ; the aniline 
colour is then added, and the mixture thickened with dextrin or with roasted 
starch. After printing, the pieces are exposed for some hours to light, which 
renders gelatin insoluble in contact with chrome. The gelatin may be re- 
placed by a solution of casein in a small quantity of ammonia. 
An important Change in the Alkali Manufacture . — It seems, according to 
R. Wagner, that Leblanc’s process is about to be superseded in England, 
Austria, and Germany. A solution of chloride of sodium is converted by 
bicarbonate of ammonia into chloride of ammonium and bicarbonate of soda ; 
the latter crystallises out, while the chloride of ammonium remains in 
solution. This chloride of ammonium is distilled with limestone, and yields 
