268 Scientific Intelligence. 
less soft. The same effect takes place actually with many 
as grains, resins, wax, caoutchouc, gutta percha: it is simply a sofien- 
ing by heat, and hardening by cold. rd) 28 
Bread quite stale may be rendered tender after exposure in an oven, 
heated to 70° C. (158° F.) M. Boussingault has shown that the soften- 
ing may be produced at a temperature between 50° and 60°C., a 
take place a number of times. The loss of water is of very: 
amount. M. Boussingault has observed that bread will become stale 
even when kept in an atmosphere saturated with moisture. 
Chemical Papers read before the Academy of Sciences.—Many com- 
munications have been made to the Academy of Sciences since my last 
communication. Several of them have especially a theoretical bearing 
and cannot be analyzed in this place. Of this nature is a memoir of 
the uric chlorosulphalic and percarbonic compounds, by M. Laurent, 
whose impaired health now for two years has weakened his physical 
vigor, but without diminishing his relish for science, or his passion for 
research. Another paper is on an application of the theory of achro- 
active, in spite of his 80 years. There are also notes by M. Babinet, 
and M. Zantedeschi, on the longitudinal lines of the spectrum, ete. ete: 
Electrical Machines.—The common electrical machine,so much neg 
lected since it has been dethroned by the pile, still receives from time 
to time some little improvement. It will be remembered that a means 
of avoiding the influence of atmospheric humidity, by covering with a 
thin layer of tallow the glass supports of the conductors, was !tfo- 
duced by M. Munch of Strasburg, a physicist who invented a pile that 
bears his name, the pile of Munch. 
Under the hands of M. Provenzali of Rome, the electrical machine is. 
in the way of new progress. This physicist has found that aia 
of moist air and give always a considerable quantity of electric 
In order to a the se sparks, it is necessary to have the insu 
lating sheet strongly electrized. ich i very 
M aper.—It is well known that paper pie ing 
white when first made, often becomes yellow some time serie | 
used. The yellow color is not always uniform, but as iat. Io 
> ; a : 
