. Scientific Intelligence. 
The working mixture is sulphuric acid and water, the strength varying 
with the temperature, and the amount of work to be performed. ave 
found a wine-glass of acid to three quarts of well-water, at the temper- 
ature acquired by standing a few hours in a room at 70° Fah., to answer 
very well, when the surface to be plated did not exceed 14 square in- 
ches. ‘The silver solution is made by dissolving cyanide of potassium 
in water, and adding thereto the oxide of silver. The ratio of the in- 
gredients I am unable to state, as I have not hitherto directed my atten- 
tion to this point, but have prepared the solution by trial until I obtained 
the desired result. 
By the process above described, we can at pleasure transfer the 
tints of the pearl to those pure metals, which will best preserve their 
brilliancy, and while the knowledge of this fact is interesting as a mat- 
ter of science, it may perhaps be well for the artist to consider if it 
cannot be applied to some ornamental purpose, and the beauty of the 
precious metals enhanced, by teaching them to glow with the richest 
hues of light. 
26. On the Volumes of Atoms and their Relation to the Position of 
the Elements in the Electro-Chemical Series; by M. Avocapro, (Bib. 
Univ. Genev. June, 1845, p. 182 ; from Mem. Acad. Roy. Turin, Vol. 
viii.) —The author gives the following table, and demonstrates that the 
order of the elements which it presents, is in general their order in the 
electro-chemical scale ; and such discrepancies as appear, he believes 
will be removed when the molecular volume is more accurately deter- 
mined. 
MOLECULES, DENSITY, —— betes: 
NAMES OF SUBSTANCES: | oxygen=1m. | water =1d." | molecular —- meer 
055 1-40 0395 0-612 
1:98 4:95 0:399 0-618 
1:22 3-00 0-407 0.632 
1:50 3:50 0-429 0-665 
1:00 2-00 0-500 0-775 
0-98 1-77 0-553 858 
6:66 11-70 0:569 0-882 
12°33 21-50 0573 0:889 
651 11-10 0-586 0- 
12-44 19-50 0-638 0-989 
12-43 19-26 1 
6-76 10-47 0-645 
5 6-29 ‘01 0-785 1-218 
12-66 15-50 0-817 1-266 
4-70 “15 0817 1-267 
7:38 0- 1-346 
7-40 40 0-881 1-366 
6-78 1-382 
7-92 8-80 0901 1-396 
735 -29 1 1-563 
12-94 11-40 1 1-760 
8-06 00 1-151 1-785 
1-22 0-86 1-424 2-209 
1-45 0-97 15 2-325 
