542 Progress in Science. [October, 
a sudden change occurs, and the amount of gas given off becomes considerably 
diminished. In the case of cyanogen the absorption takes place very rapidly, 
being confined almost entirely to the first ten minutes, and the curve repre- 
senting the absorption between o° and 80° is continuous: the results obtained 
may be given in tables, and also represented by absorption curves. Hydrogen 
and nitrogen are very slightly absorbed by the charcoal. 
M. Daubree gives the following result of his examination of the rocks of 
native iron which were discovered in Greenland, in 1870, by M. Nordenskiold:— 
WIGAN We Se Se oo MOo- de oo oo. .oo “ery! 
Iron combined with oxygen, sulphur, and phos- } 71°000 
OMS go oe. 66 oa oo GO 50 05 vn SYOMONG 
Carbonsicombined 0 ee sell ol eet sn tee OOO ‘ 
< AECI US ess) feck fovap ers Lee yee) ee Seek 4/064 
Nickel Se tata tise ae sk. efeu 2OOS 
Cobalt Se ers en AeiEN) BORN Min: O'OGE 
SUNOS Go. so oG oo 9Gd oo co Se So os BORE 
Arsenic Sean Lo aONn PDR to MOCMENS EO eG. | OOD 
Ios “Bd Go do oo co oo SO 56 od oo GORE 
SHINGO Bach oa oo oo CO fad! oom co co ldo no *OO7E 
INDINREREN GG go 06 of 55 GO oC co Sa oo vo GWO 
(Osage) S55 pO 6O oo co 06 o5 ob oo 5a BRS 
Combined wate Bre PO Oounocnn ocn OousEnos = so” oo. OLS 
labyeoNNe WeIKee5 O65 oO oO O65 ob os co oo OBL 
Sulphate of lime .. .. 1°288 
Soluble substances —| Chora of calcium .. e30) 1°354 
ay COD ALOR yy.) re) OLO2T7 
Chromium, copper and loss .. Ms I‘OOI 
A process of printing on cotton or silk, which promises to be of practical 
utility, has been devised by M. Vial, of Paris. The cloth is first washed over 
with a solution of a salt of silver; then a coin, a medal, or a metal design 
—the metal being more elettro-positive than silver—is placed upon it, and 
the design is produced by a deposit of silver in black lines in the fabric. 
