416 Scientific Intelligence. 
The cause of these dislocations is to be sought, according to Weiss, in 
a one-sided absorption which each line undergoes toward the violet end 
of the spectrum, when the deosies of the body is increased. This is shown 
by direct observations and comparisons with the solar spectrum as well as 
by numerous measurements. There is no specific absorption upon both 
sides of each line, but only an absorption upon the side of the line which 
lies toward the violet end of the spectrum. In this manner the bands 
ecome broader and the distance between them Jess. The author has ob- 
served similar changes in the breadth of Fraunhofer’s lines at sunset. In 
this case also the absorption was only upon one side. From this it appears 
that the lines of ee ee, acid cannot be used as standards in vet 
— of indices, &e.—Pogg. Ann., cxii, p. 153, Jan. 1861. 
Note on Dr. J. SeGuies ‘Paper on the i influenc + of M 
docsas on the ane of a jet of Coal Gas, it his Jour. [2], xxv, pres wit. ch 
an experiment by Dr. Charles ‘Sondhauss, ie of the Realschule of 
Neisse, {in a letter to Dr. William Shars ood).—* The observation of 
a 
particles of an or body, particularly at the high temperature of flame. 
Such an hypothesis, however, seems to me unnecessary as an explanation 
of the chensasiees. ; nor does this theory demonstrate that the gas-flame 
is a body different from air:—in which case the flame would be removed 
from the external tendency to oscillation, and by its own oscillation would 
even bring the pap tigen air or gas column into a state of fluctuation 
and singing, as in the case of the chemical harmonicon 
Thus a flame operates ‘to surround and hold together the gas column 
as a separate body, This becomes quite evident from the following ex- 
periment which I have devised. 
1. i mp sets a _ ~~ if the following 
a | Mier fig. 1, or fig. 2, w is open at both 
€ ends. Tait of hie uaa (c), is placed 
Nm close toa small flame of an alcohol thie, 
Bs (2): with the mouth fixed at (a), 1 blow a 
b : d slow current of air, when there is produced 
a 
a loud whistling tone, the pitch of which is 
oores by the dimensions of the appara- 
, a8 well as by the force with which the 
current of air is produced. The dimensions of t — ass tube used b 
e, are, 150-240 centimetres long, the opening at (c), 2-5 millimetres 
wide, and the diameter of the cylinder or spherival a PO a (b, ¢), 
amounts to 1-§-2°2 ctm. 
If we blow a current of air through such a glass a nar employ- 
ing the flame as above, there will be produced only a roaring —" 
which there is perceived a tendency to the production of nasi a to 
ote wood. physieists, who may be inclined 
to take up the investigation of singing flames, ete, I would suggest, 
that, the phenomena may be most conveniently produced, by sounding 
two imperfect intervals ip unison, on the flageolet, By two imperfect 
intervals in unison, I mean ,two-tbinds in n unison, one tuned a little flat of 
the other. _ 
