476 
NATORE 
| Marcit 14, 1907 
Tue sixth annual students’ soirée 
Technical Institute will be held on Saturday, March 106. 
The programme includes special demonstrations and short 
addresses on scientific subjects in the laboratories and 
workshops of the institute. 
On April 23, the University of Glasgow will confer the 
honorary degree of Doctor of Laws upon Sir George Watt, 
author of the ‘‘ Dictionary of the Economic Products of 
India’’; Prof. E. Boutroux, Paris; Prof. J. Norman 
Collie, F.R.S.; Prof. U. Dini, Pisa; Prof. J. H. Poincaré, 
Paris; Prof. John G. McKendrick, F.R.S.; and Principal 
D. Macalister. 
Tue estimated expenditure on education, science and 
art, for the vear ending March 31, 1908, is given in the 
Civil Service Estimates, recently issued, as 17,495,237/., 
which is a net increase of 316,955/. upon the grants made 
in the fiscal year just ending. The following extracts 
show how some of the estimates compare with the grants 
made in the preceding year :— 
1607-8 Compared with 1906-7 
Increase Decrease 
& & 
Board of Education 13,593,046 254,046 ... — 
British Museum 171,041 1,043) ---) 
‘Scientific Investigation, 
Xe. Gab See | ect S008 54,479  «- — ... 3,171 
Universities and Col- 
leges, Great Britain, 
and Intermediate 
Iducation, Wales 201,400 1,000 — 
Public Education Books 
land) ofa Ve ts. 2,022,554 50,426 — 
Public Education ‘(Ire- 
land) eee er ne AOS GCOS G0 J — 
‘Queen’s Colleges (Ire- 
land) sag dn O00 4) 700 mane = 161 
The apparent decrease in the estimate under scientific in- 
vestigation is explained by the fact that in 1906-7 the grant 
to the National Physica! Laboratory for new buildings and 
equipment was 10,000l., instead of the 50001. to be granted 
fo the laboratory in 1907-8. 
Tue executive committee has submitted to the trustees 
‘of the Carnegie trust for the universities of Scotland its 
sixth annual report, which is concerned with the adminis- 
tration of the trust during the year 1906. Under the 
scheme of allocation for five years of an annual grant of 
40,0001. among the four Scottish universities, which be- 
came operative on January 1, 1903, sums of 37,2891. were 
claimed and paid during 1906. The grants for library 
‘purposes and for provisional assistance in teaching 
amounted for the year to 64001. For buildings and per- 
manent equipment the grants for 1906 reached 26,180]. 
Payments towards teaching endowments to the extent of 
4700l. were made, and there is under this head an un- 
‘expended balance of 25,132/. Under the scheme of endow- 
ment of post-graduate study and research, appointments 
were made to seventeen fellowships and to thirty-seven 
scholarships. Grants of varying amounts were in addition 
paid to forty applicants. The total expenditure under this 
scheme was 6303/. during 1906, and it is estimated that 
during 1907 8064!. will be spent. The expenditure upon 
the Royal College of Physicians laboratory during the 
year was, so far as the trust is concerned, 314l.—this 
amount being independent of the capital invested in taking 
over the property of the laboratory buildings. The report 
directs attention to modifications in the scheme of pay- 
ment of class fees adopted last year by the committee; 
the first limited payment of fees of further classes to those 
beneficiaries who had passed their graduation examinations 
up to date, and the second modification limited payment of 
fees of advanced classes to those who had proved their 
ability to profit by such classes. A striking diminution 
in the number of beneficiaries and in expenditure upon class 
fees followed the adoption of these modifications. The 
report is provided with extensive appendices, which supply 
detailed information concerning the numerous activities of 
the trust. 
T950, VOL. 75 | 
of the Sir John Cass | 
SOCIETIES AND ACADEMIES. 
Lonpon. 
Royal Society, December 13, 1906.—‘‘ The Velocity or 
the Negative Ions in Flames.’’ By Ernest Geld. Com- 
municated by Prof. H. A. Wilson, F.R.S. 
The experiments described in this paper may be re- 
garded as a continuation of the investigations of the 
properties of ions in flames carried out by Prof. H. A. 
Wilson in this country and by Marx and Moreau on the 
Continent. 
The determinations of the velocity of the negative ions 
previously made had led to the conclusion that the ions 
were of the nature of corpuscles loaded with electrically 
neutral molecules. The present series of experiments shows 
that this is not the case, but that the ions are probably 
free electrons. 
The first part of the paper gives an account of experi- 
ments made with platinum dise electrodes immersed in a 
flame obtained by burning the gas from a large Bunsen 
burner at a row of holes in a quartz tube (quartz for 
insulation). It is shown that the conductivity of the 
flame is unaffected by putting salt on the electrodes, 
although the current is increased from 7:3X10-° to 
261xX10-° ampere, a result which enables the gradient to 
be determined from the current. 
The value of the conductivity obtained and the number 
of ions per c.c. deduced from experiments by Prof. Wilson 
and the author (Phil, Mag., April, 1906) enable an approxi- 
mate value to be found for the velocity of the negative 
ions in an electric field. The velocity so obtained, 
8000 cm. per second for an intensity of one volt per cm., 
was of a different order from those previously obtained 
(1000 cm. per sec.). 
The latter had been found on the assumption that for 
small potential differences between platinum electrodes the 
gradient in the flame was uniform from electrode to elec- 
trode, the very close way in which Ohm's law was followed 
for small applied E.M.F.’s serving as a foundation for the 
assumption. The measurement of the gradient for applied 
E.M.F.’s of the order of one volt across 5 cm. is com- 
plicated by the variations in the potential taken up by a 
platinum wire in the flame, due to changes in the tempera- 
ture and ionisation. These changes are large compared 
with the quantities to be measured, and ordinary methods 
of deducing corrections leave possible errors of the same 
order as the corrected quantity. To avoid this difficulty 
a special arrangement was adopted in which, by using a 
thermocouple as explorer, the actual variations due to the 
applied E.M.F.’s were separated from the incidental vari- 
ations in the flame. It was found in this way that the 
fall of potential consisted of a rapid drop at the electrodes, 
at the negative electrode for the free flame, and at the 
positive when salt was vaporised beneath the kathode, 
together with a uniform gradient in the body of the flame. 
The results so obtained gave the gradient necessary to 
drive the ions of salt vapour from the kathode to the 
anode while they travelled upwards with the stream of 
as. 
If v is the upward velocity of the flame gases, h the 
height of the electrodes, d the distance Renneen them, and 
x the distance the salt vapour extends from the kathode, 
the velocity k, of the negative ions for unit electric field 
is given by k,X/d—x=v/h, where X is the gradient found 
as above. The velocity v of the flame gases was found 
by photographing the images of bright particles in the 
flame formed by reflection ‘at a plane mirror attached to 
an electrically-driven tuning-fork. 
The value found for the velocity 
for a gradient of one volt per cm. 
12,900 em. per sec. 
The velocity of a corpuscle of mass m and charge e in 
an electric field of intensity X is NeA/mu, where A is the: 
mean free path and wu the mean velocity of agitation of 
the corpuscles. Taking for e/m, A, u, the values 10’,, 
3X10-*, 2-32X10’, respectively, we get for a field of one 
of the negative ions 
was found to be 
volt per cm. a value 13,000 cm. per sec. nearly, a result in 
close agreement with the value for the velocity of the 
ions found experimentally. It appears, therefore, that the 
