M4 - Scientijic Intelligence. 
paper, which is not covei'ed with tin, and having dried it, but 
without taking away from the paper its own natural humidity, 
he covers this face with very dry oxide of manganese. The 
pile being then constructed, it is carefully defended from the 
air. If the paper is not line and unsized, a little alcohol 
should be added to the solution of sulphate of zinc. The best 
manner of preserving the pile, as Zamboni has ascertained by 
long experience, is to inclose it in a glass tube, whose diameter 
is a little greater than that of the discs, and to run into the 
intermediate space a moderately warm cement of wax and turpen- 
tine. A pile of 2000 discs constructed in this manner, gives a 
spark visible in day light. M. Zamboni recommends the per- 
fect insulation of all- the parts of the pile that require to be in- 
sulated. — Gilbert’s Annalen der Physik, tom. ix. p. 151. 
8. Hare’s Galvanic Instrument called a Calorimotor. — Dr 
Robert Hare has laid before the Academy of Natural Sciences at 
Philadelphia, an account of a new galvanic instrument, which 
he calls Calorimotor , from the idea that the principle of galva- 
nism is a compound of caloric and electricity. It consists of 20 
copper, and 20 zinc plates, about 19 inches square, supported 
vertically in a frame, the different metals alternating at half an 
inch distance from each other, as shewn in Plate IX., Fig. 8. 
All the zinc plates are soldered to a common slip of tin, and 
all the plates of copper to another common slip of tin, so 
that each set forms one continuous metallic superficies. When 
the copper and zinc superficies are united with an interve- 
ning wire, and the whole immersed in a vessel containing 
an acid solution, the wire becomes intensely ignited; and 
when hydrogen is liberated, it usually takes fire, emitting a 
very beautiful undulating or coruscating flame. By means of 
iron ignited in this apparatus, a fixed alkali was decomposed 
extemporaneously. When hydrate of potash was applied 
to the connecting iron wire while in combustion, by placing it 
m small pieces in a flat hook of sheet iron, the evolution of pot- 
assium was demonstrated by a rose-coloured flame. — See Ame- 
rican Journal oj Science^ No. IV. vol. i. p. 413. 
9. Stdzer’'s Galvanic Experiment in 1767. — Sulzer, inhis 
Nouvelle Theorie des Plaisirs, published in 1767, has given an 
accurate account of a modern galvanic experiment,, which is well 
