Chemistry and Physics. 115 
select from various methods given by the author those which he found 
most advantageous). For the preparation of anilin, 1 part of nitro- 
benzin, 1-2 parts of iron filings free fi a n- 
centrated commercial acetic acid are introduced into a capacious re- 
t tic acid must be free from mineral acid and its quantity 
must be sufficient to completely cover the iron. The action quickly 
begins without heat and becomes so violent that the liquid boils and 
exc a concentrated solution of caustic potash is to be added to 
the distillate; hydrated anilin separates upon the surface in a very 
nearly pure state. The quantity of anilin obtained by this process is 
almost ? of the nitrobenzin employed, an the author states that anilin 
the action has ceased the retort placed in a sand-bath so that the belly 
shall be eatinlataly covered. The acetic acid distills over first; the 
naphtalidin comes over at 300° and-condenses in an oily liquid beneath 
the acid which protects it from the air. ‘The two are to be separated by 
& second distillation, and the naphtalidin preserved in a tightly stoppered 
ttle. It is remarkable that the compounds of protoxyd of iron oe 
prs acids do not decompose the nitro compounds.— Ann, de os 
et de Physique, xlii, 186, Oct. 1854. 
7. Prof. Tyndall on some Peculiarities of the Magnetic — (Proc. 
Brit. Assoc., 1854, Ath., No. 1405.) —The Professor said, a piece of soft 
iron suspended bien eeeit’ the flat poles of an electro-magnet set wa asad 
dimension from pole, the residual rt ih of the cores being suffi- 
cient to produce the effect. This is the normal deportment of mag- 
hetic bodies, but it is by no means ania: By mechanical agency, 
by pressure for exa mple, the structure of a magnetic body can be so 
modified that its shortest horizontal dimension sets from pole. Prof. Tyn- 
dall exhibited actions of the kind where the body operated on was com- 
Pressed magnetic dust. In such a body two opposing tendencies were 
at work,—the tendency due to length, which sought to set the length 
axial, and the t tendency due to structure, which sought to set the: line 
east ois to the length axial. Between the flat poles the latter ten- 
Fy 
n 
a=) 
— 
2°] 
Qa, 
° 
2. 
fo] 
t=.) 
=] 
s 
Ee 
=] 
- 
rh: 
ae 
oO 
i= 
"SS 
2.3 
= 
oe 
o 
— 
an] 
=. 
- 
=. 
wa 
= 
io) 
>) 
5 
° 
~~ 
ta) 
tendency which was a ue to structure, and to draw the mass into the 
axia — But in raising or lowering the body operated on out of the 
Phere of this local neath by bringing it into a position where the 
distsibutio on of the magnetic field resembled that existing between the 
flat poles, the body forsook the axial position and turned into the equa- 
torial. The complementary phenomena were exhibited by bismuth. 
A tiorn tmal bar of this substance sets its length at right angles to the line 
