258 Correspondence of J. Nickles. 
sulation of the wires was no longer perfect. Finally a heavy sea caused 
the cable to break at the tangled bights, and all hope of recovering 
the cable then out was given up. A large amount of cable remained 
sto 
rough, and the vessel could make but little headway ; and they were 
forced to so many deviations from their course that it was evident they 
would not have length enough to reach Galita. Their only course, 
therefore, was to cut the cable and return and wait for a more propi- 
tious season. 
Such is the history of this peg undertaking. Mr. Brett would 
have been successful during the months of January, July or August; 
but the terms of his engagement enlist not admit of his waiting, except 
before an. impossibilit 
The operation will be taken up anew by the French government ; 
and as they have required that the line should end at oe na, the cable 
will have to be 200 miles long. Mr. Brett proposes, as a change, that 
in place of seven c nducting wires, the cable should bitte only three, 
which will suffice for the existing necessities of correspondence. The 
cable will then weigh only five tons per mile in place of twelve; at the 
same time more care will be expended on its construction. ‘T his pro- 
ject is accepted, and the construction of the cable for uniting France 
and meer is going on with all despatch. 
nium and Silicium.—The memoir of M. H. Rose on the prep- 
eration of a ae from cryolite has been the mean s of important 
mprovements in this manufacture. Deville had Gecnighil that with 
she addition of Auorid of calcium to the bath of the double chlorid of alu- 
minium and sodium, aluminium may be obtained, while it Is not possi- 
ble with the chlorid alone. The fluorids are therefore excellent solvents. 
i 
sodium, while silica is decom ; as even ese sodium by 
bringing together capillary glass ae sodium in r. But the great 
difficulty in t experiments is in the nature of the vessels used for 
the experiments and the eaersbiity of the electrodes. For gas carbon 
is dissolved rapidly in the baths of fluorids when it is used in the prep” 
aration of silicium 
Alousionens is “manufactured now on quite a large scale at Amfre- 
ville near I _ The vapors set free in this process are very ratege 
st:  chlorid of silicium, chlorid of aluminium, chlorid © 
h gg ae acid. These are disposed of by interposing 
ye a furnace of lime, heated by an adjoining fire, into 
