POT 
Potassa, Davy’s original mode of 
decomposing, xxi, 367.f 
, action of, on organic matters, 
xvil, 882; xxiv, 372. 
, action of, on cholesterine, 
xliv, 60. 
and soda, mixture of pure car- 
bonates of, xlix, 195. 
, carbonate of, mode of prepar- 
ing, free from silica, xlix, 195. 
, chlorate of, mode of obtain- 
ing, ix, 201. 
, pure chromate of, xx, 409. 
, to test the chromate of, S. 
Zuber, xxiv, 372. 
, chromate of, means of deter- 
mining the purity of, xvi, 392. 
; , atest for distinguishing 
strontia and baryta, xxxvi, 183. 
, bichromate of, ulcers pro- 
duced by the use of, xvi, 384. 
, manganesiate of, F. Wohler, 
xxviil, 137. 
and copper, sulphate of, xx, 
195. 
and silica, new compound of, 
xvi, 397. 
Potassium, atomic weight of, xlvil, 
189. 
——.,, preparation of, vill, 372. 
, best method of preparing and 
preserving, xix, 205.f 
, new apparatus for obtaining, 
L. D. Gale, xxi, 60.f 
, improvement in Brunner’s 
process for, R. Hare, xxiv, 312. 
, an improved mode of obtain- 
206 
ing, R. Hare, xxxvill, 338; xl, 
Par 
, properties of, xvii, 182. 
——,, price of, in 1825, ix, 387. 
, experiments on, by J. T. Du- 
catel, xxv, 90. 
, ammoniacal nitruret of, xxv, 
205. 
, iodide of platinum and, W. 
W. Mather, xxvii, 257. 
—., preparation of iodide of, ix, 
188. 
, ferrideyanide, deoxidation of, 
C. F. Schénbein, xlix, 203. 
P O.W 
Potassium and naphtha, explosive 
compound produced from, xxiv, 
315. 
, mode of filling tubes with, 
xxiv, 316. 
Potatoe, found wild in South Amer- 
ica, iv, 195. 
, fruitfulness of, iii, 881. 
——., culture of, in France, xxvil, 
176. 
, on the growth of, xi, 170. 
——, precaution in planting, xxi, 
159. 
, butrition from, EL. Ives on, 
Pi One 
———, mode of preserving, vi, 200; 
xvi, 188. 
, how to boil, xxiii, 201. 
——, used in steam engine boilers, 
vil, 193. - 
, oil from spirits of wine of, 
XXvill, 3886. 
, essential oil of, A. Cahours, 
XXX11, 082. 
cheese, xvili, 895; xxiii, 202. 
flour for bread, xvi, 391. 
, detection of, in wheat, 
xvil, 173. 
, molasses from, S. Guthrie, 
xxi, 93. 
— starch, sugar from, S. Guth- 
rie, XXi, 284. 
» Sweet, sugar in, xv, 285. 
fly, cantharidin in, 11, 137. 
Potentilla supina, xiv, 114. 
Pot-holes, made by means of run- 
ning water, in the Green Moun- 
tains, vi, 252. 
, near the Franconia Notch, 
XXXIV, 122. 
Potosi silver mines, xxiv, 233. 
Potstone, Middlefield, Mass., vil, 51. 
of Greenland, xvii, 14. 
Potter, C. E., notice of a rocking 
stone, xxiv, 185.f 
‘Pottery, analysis of, xv, 183. 
, notice of A. Brongniart on, 
xxxi, 134. 
, ancient American, xxvil, 175. 
Powder of Cassius, purple, see Cas- 
Situs. 
at 
