Chemistry and Physics. 391 
graphs in which Venus was ipa on the sun. The combina- 
tion of all these may be expected to give a result of equa 
weight with either of those aiteaty mentioned. I think, there- 
fore, that we may look forward with considerable certainty to 
seeing the probable error from the combination of all the obser- 
vations less than 0’ 02, and, perhaps, not much more than 
0-01. At the same time, it is not to be disguised that there is 
a possibility of unforeseen perturbing causes being brought to 
light by a comparison of all the ark which will upset 
all our @ priort estimates of probable error. 
SCIENTIFIC INTELLIGENCE. 
I. CHEMISTRY AND PHYSICS. 
1. On the Occurrence of Diphenyl in Coal Tar.—Fittig com- 
municates the results of an investigation made in the Tubingen 
170° and others boiling above 200°; whence the conclusion that 
coal tar contains no considerable quantity of a hydrocarbon boil- 
ing between these limits. The second fraction gave a more satis- 
factory result. After several ee of five degrees, the 2a 
d 2 
Os 
hydrocarbon melted at 70°-71°, and exhibited all the Sie sich 
of diphenyl.— Ber. Berl. Chem. Ges., viii, 22, January, 1 
2. Explosiveness of methyl nitrate.—Methyl nitrate was Sake. 
Dumas and Peligot in. 1835. In 1862, Carey Lea* showed 
that it could advanta conaly Whe eet methyl iodide in most ata 
cal loner erin ally in ipso on oH the methyl base 
In 1864, as nee of ‘thia servati ugo Liwenstein 
la it in 4b chinidtalAtite of the: wiles dered from rosin 
substitution ; cone it has since come so extensively into use as 
by a proadhont nd since, acta sate cys re saline on a large 
Scale in the case of the dently of the talent young chemist, E. 
* This Journal, I], xxxiii, 86, 227, 1862. 
