i Mi i Se ae es ee 
ee ene ee Oe eee 
Pa eee 
Agricultural Chemistry. 419° 
5. Miscellaneous facts. ee the other facts worthy of notice in 
recent photographic journals ar 
1.) Use of formic acid in ies reloper for instantaneous views, but with 
somewhat discordant testimony as to its value. 
(2.) Methods of Ae prego the albuminous film from the positive 
ven and applying it to the surface of porcelain or other ware, when 
e gold and silver image may be burnt into the enamel. Similar 
efieee have also been obtained with carbon prints. 
(3.) Substitution of the double sulphate of tron and ammonia for 
green vitriol in the developer (5 parts of the salt, 20 parts of No. 8 
acetic acid, to 100 parts of —— which is said to have important ad- 
vantages over the usual developer 
4. the wet process, after removing the plate from the silver bath, 
armen it in a large bath of distilled water, and, just before using, dip- 
Ing again in the silver bath. The sensibility i is said to be thus in- 
creased 50 to 100 per cent,.and freedom from pin holes and stain to 
better insured. 
5.) A new process for printing positives is said to have been in- 
vented by Mr. Wothly, in which chlorid of silver is replaced by less 
expensive materials, and the cost reduced 70 to 80 per cent, with the 
very great increase of sensibility; but the details were not given, as 
the author wishes to secure beg interest by patent. 
(6.) The use, in the tannin process, of acetic acid in the Fiver bath 
se 
developer, which protects the white of the image, ae also diapiel 
the plate in the silver bath just before developing, ‘and er it has been 
dipped into distilled water. P, C., JR. 
Ill. AGRICULTURAL CHEMISTRY. 
1. On the Epibr i esis reer of Gypsum.—Denéxatn, in a note A see 
sented to the Academy of Sciences at Park ( Comptes ee 18 May, 
1863), gives ‘hes results of some new studies on this much discu 
question. The idea that plaster favors the production of ee in the soil 
is not sustained by Dehérain’s experiments, as he found that vebep sg 
went on as slowly in plastered soil as in soil destitute of gypsum 
also found that gypsum is without influence in assisting the formation of 
ammonia in the soil, and unlike caustic lime, does not favor the solution 
of phosphates. 
Deni ioed that the fertilizer in aes — almost exclusively by 
its effects upon the soil, and observing that those crops which are most 
es by plastering, viz: the Leguminose, peta a large amount of 
Dehérain was led to inquire whether gypsum exercised any 
daben effect on tes substance in the soil. For this purpose a variety of 
soils were hep 1st, in their natural state, and 2d, after mixture with 
10 per ¢ of erpeneh this lege = ie being cision to ce 
Be. oy ¢. Pagans 
a preservative tical of an eve ng. ye, on organic ‘matters, 
a whole 
that gypsum has 
By te, sable dung, it is said, may be ke peas uite fres and unaltered for 
year, though it 
uires an odor of a s; hydroge’ 8. W. J 
Am. Jour. Sc1.—Srconp SERIES, VoL. XXXVI, No. Wk -Nev, 1863, 
se: 
