394 
Notes. 
views, put forward before physicists had developed the theory of 
the correlation of forces, were necessarily very vague. It might 
even be conceived that in the living organism, as well as in our 
physical instruments, analogous conditions might produce either 
mechanical work or electricity. Having found that muscular acts 
are complex, i.e ., that a muscle in tetanus or in contraction exe- 
cutes a series of minute successive movements, which M. Marey 
calls shocks , which accumulate to produce muscular attraction, 
he has examined the discharge of the torpedo, and found there a 
similar complexity. Having passed this discharge through an 
electro-magnetic tracing apparatus, he found that it was made up 
of minute shocks, which recur at the rate of 150 in a second. 
Cold reduces the rate alike of the muscular and electric shocks, 
whilst heat acts inversely. Hence M. Marey concludes that these 
two functions are really homologues. The gymnotus gave simi- 
lar results to those of the torpedo. The latter fish, when con- 
nected with a telephone and slightly excited, produced a very 
short croaking. If a prolonged discharge is occasioned by 
pricking the electric lobe of the brain, the sound produced lasts 
three or four seconds, and in tonality borders upon mi (165 vi- 
brations). 
On examining with the spectroscope, both by absorption and 
by means of the electric spark, the products of his operations on 
the mixture of earths from samarskite, M. Lecoq de Boisbau- 
dran has observed rays or bands not to be referred to any element 
formerly known, and not corresponding to the descriptions of the 
spectra of the earths recently announced by MM. Delafontaine, 
L. Smith, Soret, and De Marignac. These new rays of absorp- 
tion and emission seem to belong to one and the same body. 
The emission spectrum is composed of four bands shaded to- 
wards the left and formed of narrow rays, the strongest of which 
is the most refrangible and forms the right margin of the band. 
The absorption spectrum comprises two strong bands in the blue, 
and several rays of less importance in the green. The metal 
which yields these new spectra is precipitated as a double potassic 
sulphate along with didymium ; its simple sulphate is rather less 
soluble than that of didymium ; its oxalate is precipitated along 
with didymium, but ammonia separates the oxide of the new 
metal before that of didymium. 
An improvement in Bunsen’s battery is described in “ Les 
Mondes” by M. Lefebure. The oxidation of the exterior surface 
of the zincs contributes nothing to the liberation of electricity, so 
it may be safely covered with varnish, thus reducing the con- 
sumption of zinc by one-half. 
