182 S. P. Sadtler—Analytical Notices. 
A lot of oe strontic nitrate was taken, powdered, 
and dried at 
“7345 grms. nitrate gave °6348 grms. sulphate sett 21 pr. ct. Sr. 
"9840 “ : - #eoue © " ‘21 pr. ct. Sr. 
A second lot was re-crystallized, and large ae were taken 
and dried between filter paper o 
‘3007 grms. nitrate gave 2594 grms, sulphate — ~ pr. ct. Sr. 
3641 “ * + S138." = 3 pr. ct. Sr. 
A third lot was then carefully dried ves “ie 
*3318 grms. nitrate gave eon grms. sulphate ==41°36 pr. ct. Sr. 
3184 * “ 6 ‘275 “ “ —41°30 pr. et. Sr. 
The theoretical amount Sr in Sr(No,), is 41°37 per cent. 
These results show very much greater accuracy than the deter- 
mination of sulphate by precipitation, and there is no compa ari- 
son as to the ease of manipulation and the rapidity with which 
the determination can be made. 
accurate. 
However, it struck me that the sulphate determinations by 
evaporation were so accurate and so rapidly executed, that, in- 
stead of repeatedly igniting the oxalate with a piece of ammonic 
carbonate until a constant weight was obtained, we could con- 
vert the oxalate into sulphate, and run it down to dryness with 
the “ ring-burner,” with a great saving of time and labor. 140 
test this, the following series of determinations with calcic oxa- 
sci was made by Mr. Edgar F. Smith at my request. 
e lot of’ oxalate was prepared in the usual manner, washed 
on a “filter and dried between 100°-105°. 
"1860 grms. oxalate gave *1725 grms. sulphate =27°28 pr. ct. Ca. 
2083 “ nd “ +1939 & “ 
==27°38 pr. ct. “ 
5013 “ 66 “ce “4659 “ “ — 97-33 pr. ct. “ 
| 944 “c “ “cc ‘1808 “ “ce —27°35 pr. et. 66 
be * sa ere SS . =27°31 pr. ct. “ 
nother preparation of oxalate was made and washed as 
dee and dried at 110°. Fresenius says that the oxalate does 
not part with its water until heated to 205°, but has the invari- 
able composition (C,0,)Ca+H,O. The results show, however, 
that it begins to lose water already at 110°. 
2195 grms. oxalate gave ‘2051 grms, sulphate =27°48 pr. ct. Ca. 
2432 OQ =27°48 pr. ct. © 
