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March 23, 1871 | 
NATURE 
413 

NOTES 
Mr. GEORGE BIDDELL Arry, Astronomer Royal, has been 
selected by the Council of the Royal Society ,as a fit and proper 
person to be nominated as President of that Society on the occur- 
rence of a vacancy, and Mr, Airy has declared his willingness to 
accept the proffered honour. As General Sir E. Sabine, the pre- 
sent president, has intimated his intention of resigning office at the 
next annual meeting, the election, which rests with the fellows, 
will come on at that time. We may congratulate the Society and 
English science generally on the wise choice which the Council 
have made. In scientific distinction, administrative ability, and 
honesty of purpose, the president-elect will prove no unworthy 
successor of the distinguished man of science who has now for 
so many years filled the office. 
THE Royal Irish Academy has approved of the following 
allocations from the fund for promoting scientific researches :— 
G, J. Stoney, F.R.S., 50/., ‘‘ For Researches on the interrupted 
Spectra of Gases;” Prof. R. S. Ball, 6/. (additional), ‘For 
Experiments on Vortex Rings ; ” Prof. Henry Hennessy, F.R.S., 
20/. (additional), ““ For Experiments on the friction of Fluids in 
contact with Solids ;” Prof. Thiselton Dyer, 29/7, ‘‘For Re- 
searches on Vegetable Physiology ;” Prof. Traquair, M.D., 25/., 
‘« For Researches on the Crania of Osseous Fishes.” 
Tr is stated that the appointment of Professor of Chemistry 
and Experimental Physics at the Indian Engineering College will 
be filled up by the transfer of Mr. Herbert M‘Leod from the 
College of Chemistry. We consider this arrangement one which 
reflects great credit on those who are responsible for it. Mr. 
M‘Leod has long been known not only as an accomplished 
chemist, but as one who has the rare gift of imparting his know- 
ledge to others, and he has filled the position he held at the 
College of Chemistry for many years. 
WE understand that the names of Dr. Cunningham and Mr. E. 
Ray Lankester have been selected from the candidates for the 
vacant Professorship of Natural History in the Queen’s College, 
Belfast, and that it is probable that His Excellency the Lord- 
Lieutenant will appoint the first named gentleman as successor to 
Prof. Wyville Thomson. 
WE are glad to learn that the ‘‘Zoological Research Asso- 
ciation,” concerning which we some weeks ago inserted a note, 
is now fully established. 
WE regret to have to record the death on the 7th inst., at the 
age of sixty-eight, of Mr. Henry Denny, the curator of the Leeds 
Philosophical and Literary Society, an office he had held since 
1825. It isto Mr, Denny’s untiring zeal and assiduity that the 
Leeds Museum owes its high position among provincial institu- 
tions of a similar character. Unwearied energy, a great know- 
ledge of science, and unfailing courtesy, were combined in him in 
a manner which will render it very difficult for the society to 
supply his place. In addition to the title which he held as Asso- 
ciate of the Linnean Society, Mr. Denny was a corresponding 
member of the Academy of Natural Sciences of Philadelphia and 
of the Syro-Egyptian Society of London ; honorary member of 
the Philosophical Society of Dickinson College, Carlisle, Penn- 
sylvania ; of the Yorkshire Philosophical Society ; the Black- 
more Museum, Salisbury ; and of the Norfolk and Norwich 
Museum. 
THERE are few more zealous cultivators of Astronomy than 
an Indian gentleman, Mr. Nursing Row, a friend of the late 
Admiral Manners, who has built an observatory at his own 
expense at Vezagapatam. Although he has recently suffered a 
heavy loss of property from a cyclone sweeping over his estate, 
Mr. Nursing Row sent the munificent donations of 100/. to the 
Mansion House Fund for the relief of the distress in Paris, and 
100/. to the fund for supplying seed and other aid to the French 
|Peasantry. He is also a most generous benefactor to the poor in 
‘his own neighbourhood. 
WE learn from Paris that the report which reached the 
Academy of the death of M. Becquerel, the electrician, and 
which we copied last week, is incorrect. It was his son, M. 
Dumeril Becquerel, who died during the investment of Paris. 
Dr. Pace, of Edinburgh, has commenced a course of thirteen 
lectures on Geology, descriptive and industrial, in the Mechanics? 
Institution, Glasgow. The lectures are largely attended by 
ladies and gentlemen, The study of the science in this large 
commercial city has received new impetus from {,e attractive 
and eloquent manner in which the lecturer presents it. Few, 
indeed, have the gift which Dr. Page possesses of making scien- 
tific study popular. The directors of the Institution are in- 
debted to Dr. Page for enabling them to offer such valuable in- 
struction at so small a charge. 
THE Council of the Pharmaceutical Society offers a silver 
medal for the best herbarium collected in any part of the United 
Kingdom between May 1, 1871, and June 1, 1872. The collec- 
tions are to consist of flowering plants and ferns, arranged accord- 
ing to the natural system of De Candolle, or any other natural 
method in common use. No candidate will be allowed to compete 
unless he be an associate, registered apprentice, or a student of 
the Society, or if his age exceeds twenty-one years, 
WE have great pleasure in calling attention to the letters which 
will be found in our columns of correspondence respecting the 
International College at Isleworth, and the Crawfurd College at 
Maidenhead, where instruction in science appears to be given 
with highly creditable results, 
AT the last meeting of the American Academy, a new form of 
solar eye-piece was exhibited by Prof. Pickering. A cube is 
made by cementing together two right-angled prisms of glass, 
which is substituted for the reflector in a diagonal eye-piece. By 
using a cementing liquid whose index of refraction is very nearly 
the same as that of the glass, almost all the light and heat pass 
directly through the cube, enfeebling the image so that it can be 
borne by the eye with impunity. We can thus cut off as mucle 
of the light as we please, and yet avoid all danger of cracking 
the glass by the heat, as frequently happens when a coloured. 
glass is used to absorb it. Since the relative index of refractiom 
of the inclined surface is very nearly unity, the angle of total 
polarisation is 45°, or the actual angle of incidence.* Accordingly, 
the image will be perfectly polarised, and may be varied in in- 
tensity at will by a Nicol’s prism. If we make the angle of in- 
cidence equal to 45° in Fresnel’s formula, it takes the simple form 
sin 2z 
that the reflected light = ——— in which v is the deviation of 
cos 47 
the ray in passing from one medium tothe other. Inthe present 
case if 7 = 1’OI, we find that the reflected beam equals ‘00005, 
or only one twenty-thousandth part of the intensity of the inci- 
dent ray, if 2 = 1-001, the light is diminished to one two- 
millionth. On trying the experiment, it was found that the 
image formed was coloured, the tint changing with the angle of 
incidence. This curious effect is probably due to the fact that 
the dispersion of the balsam used for cementing the prisms is 
greater than that of the glass, and hence the relative index and 
quantity of light reflected differ for different colours. Apart from 
its practical application, this instrument possesses a scientific in- 
terest as furnishing a means of making large plane surfaces whose 
index is nearly unity, and thus enabling“us to verify laws for 
whose proof we have heretofore been dependent on observations 
with gases only. 
A SLIGHT shock of earthquake was felt on Friday night in 
the North of England. In and near Manchester the shock was 
