118 Chronicles of Scrence. [Jan., 
The author mentions another ‘little practical detail in this con- 
nection. It is generally assumed that the induction-coil is unfit 
for the exhibition of those experiments of attraction and repulsion 
which especially characterize statical electricity. A great number, 
however, may be very satisfactorily exhibited by charging Leyden 
jars, and using them as the sources of electricity. Thus:—Con- 
nect a chime of bells with the knob of a large jar; connect the 
outer coating with the earth and with the negative pole of the coil; 
then bring the positive pole within striking distance of the knob, 
and charge by a few sparks. The electrical flyer, orrery, sports- 
men, and birds may be successfully operated in this way, even in 
summer weather. The coil should not be of less than six inches 
spark length. 
M. J. E. Balsamo has presented a memoir to the Academy of 
Sciences on a new Voltaic Pile. It is formed of two plates of iron, 
one plunged in dilute sulphuric acid, the other in a solution of 
chloride of sodium, separated from the acidulated water by a porous 
diaphragm. The iron of the acidulated water acts as zinc, and that 
of the saline solution acts as copper. The current, constant and of 
considerable intensity, proceeds from the property possessed by iron 
of polarizing itself differently in certain solutions, between which 
osmogenic action takes place. M. Balsamo has also tried another 
experiment of considerable theoretical interest. He plunges at the 
same time in oxalic acid two small magnetized bars of the same 
surface and of the same weight, one having its nerth pole in the 
liquid and its south pole out of it. The second bar is in the con- 
trary position. The first acted as zinc, the latter as copper, and a 
current of electricity was the consequence. 
M. Becquerel, sen., has continued his electro-capillary researches 
to which we drew attention in our last Chronicles. He shows defi- 
nitely that—1. ‘The alteration is exerted on the sides of the capil- 
lary spaces between two liquids. 2. The electricity is disengaged 
at the contact of these liquids in the capillary spaces. He has 
modified his method of experimenting. Instead of forming the fis- 
sures in the tubes, he fastens at their extremity a strong stopper 
very tightly fixed, made with filtering paper soaked in water; a 
platinum wire traverses the stopper and connects the two liquids 
together. 
M, Bouchotte has examined the electrolytic power of the cur- 
rents of the magneto-electric machine made by the Alliance Com- 
pany. When the current sent by the commutator is always in the 
same direction, the electro-motive power is that of 144 Daniel 
elements with sulphate of copper; but when the current is alter- 
nate, as in the production of the electric ight, the electro motive 
power is nz. 
