[ JANUARY 10, 1907 
262 NA TORE 
Trinity College, prosecuting research in the Cavendish Jhere is thus removed the only known exception to thy 
Laboratory. He was one of the pioneers of wireless | general rule, that the activity of radio-active eepotancess 
telegraphy, and occupies a high position in the scientific 
world owing to his experimental work on the ionisation of 
gases, the discovery of the radium emanation, and the 
foundation of the now generally accepted theory of radio- 
activity. It is expected that Prof. Rutherford will arrive 
in Manchester early in the summer with the view of taking 
up the regular duties of the professorship at the beginning 
of the session in October next. 
again brought with it conferences of teachers 
of all grades in various parts of the country. In London, 
large numbers of schoolmasters, schoolmistresses, and 
educational administrators have met under the auspices of 
the London County Council, and discussed for three days 
subjects as Yarious as silversmith’s work and the teaching 
of phonetics. In Bradford, the educationists of the north 
of England have, in well-attended meetings, ranged over 
the field of education. Associations of teachers of special 
subjects have also held meetings characterised by their 
enthusiasm. Such gatherings are to be welcomed as main- 
taining an active interest in education, and as likely to 
send teachers back to their worl with renewed energy and 
broader knowledge. It is worthy of note that in none of 
the meetings has science or mathematics taken a prominent 
part. We have no reason to regard this as indicative 
of a falling off in the interest in these important parts 
of the school curriculum; it rather directs attention to the 
fact that in recent years questions concerning mathematical 
and scientific teaching have dominated the programmes of 
teachers’ meetings, and much thorough discussion has led 
to improved teaching and obviated, for the present, the 
need for further argument. At the Bradford conference an 
important session had for its subject the development of 
technical education in a large manufacturing centre. Prof. 
Charnock, of Bradford, and Principal Reynolds, of the 
Manchester Technical School, read papers. Mr. Reynolds 
said we need more intelligence and more knowledge on 
the part of our working people. He suggested, first, the 
need for the extension of the age-limit in higher elementary 
schools to sixteen years. There is an advantage in select- 
ing in each of suitable localities of a town one of the 
elementary schools, and giving it an extended curriculum, 
staffing and equipping it accordingly, such school being 
fed from the elementary department of the school and 
from neighbouring elementary schools, and supported by 
a scheme cf scholarships. Secondly, the enactment of a 
law forbidding the employment of young people in working 
overtime until they reached their eighteenth year, so as 
to give full opportunity for attending evening classes. 
Thirdly, the establishment of one-day courses of specialised 
instruction in the technical school or college for selected 
apprentices in engineering and other similar important 
industries. He urged that the present need is a better 
appreciation of the requirements of general and secondary 
education so far as to secure a longer school life, and thus 
a more complete preparation for specialised training. 
January has 
SOCIETIES AND ACADEMIES. 
Lonpon. 
Royal Society, November 15, 1906.—‘‘The Effect of 
Temperature on the Activity of Radium and its Transform- 
ation Products.’?’ By Dr. Howard L. Bronson. Com- 
municated by Prof. E. Rutherford, F.R.S. 
A large number of investigators have attempted to alter 
the activity of various radio-active substances by subjecting 
them to very high and also to very low temperatures. 
Among all these attempts only two, so far as the present 
author is aware, have apparently given positive results. 
The experiments now described show no evidence what- 
ever of any change in the activity of the transformation 
products of radium when they are subjected to tempera- 
tures between —180° C. and 1600° C. If any change does 
take place it is very small, and cannot be more than 
I per cent. in the case of radium C for temperatures 
between —180° C. and 1600° C., nor more than 1 per cent. 
in the case of the emanation or radium B for temperatures 
between —180° C. and 1500° C. 
0.1941, VOL. 75] 
is not affected by temperature. 
““The Photoelectric Fatigue of Zinc.’’ By H. Stanley 
Allen. Communicated by Prof. H. A. Wilson, F.R.S. | 
Hertz’s observation that ultra-violet light can facilitate] 
the passage of an electric spark led to the discovery of 
other photoelectric actions. In the earliest experiments or 
the photoelectric effect of metals it was noticed that th 
action was diminished by exposure to light. Thu 
Hallwachs, who found that a metal becomes positivel 
electrified under the influence of ultra-violet light, state 
that ‘‘ old surfaces no longer show the phenomenon. ‘The 
radiation itself lowers the potential to which the plates ca 
be electrified, so that with any succeeding experiment mad 
with the same surface, the potential obtained is lower, while 
the rise to it takes place more rapidly, and the decrease is 
greater than when for the same interval of time between 
the experiments the plate was not illuminated.” This 
diminution of the photoelectric action is spoken of as the 
““ fatigue ’’ of metals under the influence of light, and has 
received attention from many physicists. 
The present paper deals with the manner in which the 
photoelectric activity of zine diminishes when the metal is’ 
exposed to light. 
The experiments described show that it is necessary to 
employ the sum of two exponential terms in order to 
obtain an adequate representation for the photoelectric 
fatigue curve of zinc. Just as Rutherford has explained 
the curves of decay for the excited activity of radium and 
thorium as a consequence of successive changes, so it is 
possible to explain the present results as due to two con- 
secutive changes. The nature of the modifications thus 
suggested is left an open question, | 
It is also shown that the longer waves of light can bring 
about a change in the opposite sense, that is to say, they 
can produce a certain amount of recovery of photoelectri 
activity. 
Entomological Society, December 5, 1906.— Mr. F. Merri- 
field, president, in the chair.—Exhibits—A. W. Bacot: 
A specimen of Catocala nupta, taken at rest at Hackney, 
November 9, 1906, remarkable for having two well 
developed tarsi on the left fore-leg. Also three Q speci 
mens of Lasiocampa quercus, L., bred from larve from 
Cornwall in 1906. One of these larve had been submitted 
to a pressure of from 11 to 30 atmospheres (405 |b. 
450 lb. per square inch) on two occasions, a pressure which 
had proved fatal at once to a frog, used as a control experi 
ment.—Dr. T. A. Chapman: A long series of Hastula 
hyerana, Mill., bred in 1906 from larvae collected at 
Hyéres, illustrating the spread of melanism in this species, 
and a diagrammatic map of the neighbourhood to explain 
its distribution in that area.—Dr. F. A. Dixey: Specimens' 
of Teracolus omphale, Godt., bred by Mr. G. A. K. Mar-) 
shall, to show that under arranged conditions of moisture 
and warmth the wet-season phase might be artificially 
induced.—Papers.—Xanthorhoé ferrugata, Clerck, and the 
Mendelian hypothesis: L. B. Prout.—The diaposematic 
resemblance between Huphina corva, Wallace, and Ixias 
baliensis, Fruhst.: Dr. F. A. Dixey. | 
at 
Chemical Society, December 20, 1906.—Prof R. Meldola,| 
F.R.S., president, in the chair.—A new laboratory method. 
for the preparation of hydrogen sulphide: F. R. L. Wilson. 
If a current of hydrogen sulphide is passed over calcium 
hydroxide a hydrosulphide is formed which can be de- 
composed by carbon dioxide, a carbonate being produced 
and hydrogen sulphide evolved.—The affinity constants of 
aminocarboxylic and aminosulphonic acids as determined 
by the aid of methyl-orange: V. H. Veley. It is show: 
that the usual mathematical expressions hold good 
namely, those of straight lines, y=kx or y=kx—b, c 
logarithmic curves, logy=logk+xloga. Acids which 
show irregularities in the Ostwald clectric conductivity 
expression (k)=a*/(1—a)V.(a=p/u,,) likewise show 
similar irregularities in the methyl-orange method.—Con- 
tributions to the study of the calcium phosphates, i., the 
hydrates of the calcium hydrogen orthophosphates: H. 
Bassett, jun. The author’s experiments show that, in all 
probability, dicalcium phosphate can only form one hydrate, 
