Chemistry and Physics. 213 
a consisted of nineteen bands, varying in wave-length from 6844 
to 6275 ten-millionths of a meter ; group #6 of eight lines, from 
6059 to 5901; group y of thirteen lines, from 5860 to 5667. 
The ordinary spectrum lines of the metal were not seen reversed 
owing to the too feeble intensity of the calcium light. Similar 
experiments with sodium led to yatta results. The blue vapor 
gave an absorption spectrum show in the blue a group of 
bands (jy) eleven in number, follow a soon after by a group in 
the red and yellow (a) consisting of twelve bands, and then 
by group (f) in the orange made up of seven bands. Sodium 
vapor in an iron tube heated to redness shows an absorption spec- 
trum in See the red, the green and a part of the blue are re- 
moved. absorption lines widen se tose! and a strong 
absorption ‘sia appears in the green. Hence only a part of the 
orange, the green and the ultra-blue are transmit — Proc. Roy. 
Soe., xxii, 362; J. Phys., iii, 344, Nov., 1874. G. F. B. 
” Preparation of Glacial Formic ashes the ordinary 
gas over lead formate, gently heated over a fre , the product 
is always contaminated with sulphur products which communicate 
an fr eoeaanae odor to the acid, and which — be removed. 
and y fractio cases Placed in a fi ixture and 
soliadied, it may ie te trated. The pure acid solidifies a 
temperature of eee ee oeered Ls er than that 
ae a water to sith ot icant acid, so phosphenglow 
may be considered either as P(OH),C, 
Which of these formulas is correct, may be determined by the 
action of pinaphhets chloride. In the first case the reaction is: 
POH),C,H,+(PCI,)-=PCI,0,H, +(POCI,), +(HCl),, 
