exxvi Proceedings of the Asiatic Society of Bengal. [N.S., XV, 
nitrate ; sn mee that glass itself contains silicon, one of 
the elem which the transmutation hypothesis regards as 
being sae of degradation to carbon. A strong argument 
against the absorption explanation is that the internal surface 
of the vessel at the end of an experiment must have been 
these experiments furnish a strong case for further investiga- 
tion, ye with the use of quartz vessels, and that mean- 
e impression left on the mind of an unprejudiced critic 
is at unfavourable to the hypothesis of transmutation. 
e come now to a series of investigations on the produc- 
tion of two inactive gases, helium and neon, as transmutation 
passed over because the precautions observed were not such as 
were subsequently found to be necessary. We md therefore, 
start with the observational evidence recorded by Ramsay in 
mainly of nitrogen, and contained in addition 0-726 % of argon, 
0°233% of neon, and 0°030% of helium. The corresponding 
figures for atmospheric air are: argon 0°932, neon 0°012, and 
helium 0:0004. The inactive gases in the water may have been 
derived from the atmosphere, or by radioactive changes. The 
only known source of argon and neon is atmospheric air, 
whereas helium is one of the commonest products of radioactive 
change. The water in question contains dissolved radium, an 
is saturated, coe the ae a obtaining, with emanation. 
The helium, which is prese nt to the extent of 73 times the 
amount in atmospheric air, Go certainly derived from 
this radium and emanation ; the argon, which amounts to three- 
present in air, is not so easily accounted for. If it is of atmos- 
pheric origin there should be a correspondingly large propor- 
tion of argon also: if it is not from the atmosphere it must be 
a product of radioactive change. In support of the latter 
alternative, Ramsay found that emanation which had been left 
to decay in an wets — of thorium nitrate, or simply 
in water, gave rise to n when the most stringent precau- 
tions were taken against tie entrance of traces of air. In one 
such experiment, the neon spectrum Shee ok. was more bril- 
liant than that of the neon from 0°5 c.c. of air, whilst the argon 
_ Spectrum was invisible unless a jar and spark gap were inter- 
posed, when the blue lines became just visible. 
