280 Scientific Intelligence. 
ine ’—Barlow.] Its strength and power of resisting the seth mois 
seem also specially to adapt it for the use of architects and xr eens 
usage; also 
e envelopes of letters and for cartridges. In thin leaves it affords 
admirable tracing paper. As a material for binding books it will without 
doubt be extensively used. The ease with which it rec ceives both 
— ordinary writing ink is remarkable. For so laboratories 
serves, Dexiaen es, ete. 
ent-paper has been successfully manufactured on the get 
a ae or more by the firm of De LaRue, the numerous dif 
ance of one of its members—the distinguished chemist | 
Rue. ipeoiten: shes of the parchment-paper accompany Hotim 
memoir.—F. H. s. 
2. Weighing of Moist Precipitates ; by FerpinayD F, Mave 
Ch. Méne, of Creusot,* gives a mode of weighing which does aw 
2 
precipitate ete y a Gelariation: and then in siredlles 
into a bottle, the exact en eat of sign when filled with tailed valet : 
precipitate, and the difference between the = weights fu! 
means of calculating the weight of the precipita ed 
In case the precipitate settles but slowly it apn "be collect the b 
and together with the filter, after washing, be introduced ™ into 
taken in account. Precipitates soluble in or affected by W 
weighed in some other liquid. we 
This method, of which th the above are the outlines, is spoken of mee 
Jahresbericht der Chemie for 1858} in rather diay ie to Mr. Méne, 
consider it not more than justice to the method, i Sandon neo +a 
to prove its correctness, the _ so as I have applied the p | 
large scale as far back as 18 ‘ 
I engaged in that year in Be manufacture of eee condition wit 
refuse sulphate of lead, by treating the latter in a pulpy ned very T= 
carbonate of soda. The sulphate of lead I used jatter it bad 
ing proportions of water and soluble impurities, from W e a thio pal 
first to be freed by washing. Jt was then in the ipa Jead, 88! 
and the difficulty was to find the amount of dry sulp’ 
was a matter of importance to use as little carbonate «a 
tain as pure a carbonate of lead and sulphate of soda b 
could only be done by weighing it as a whole, or in portions; P 
* ie, Oct. 1858. 
| | PRRSRSE Ghelby Wi as for 1858, P& 
