SCIENTIFIC SUMMARY. 
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conversion of thermic into electric potential ; and if so, there should he a 
loss of current in the first instance, and again in the second. And such, 
says Mr. Brooke, u appears to he the fact.” u On duly balancing the thermo- 
element above mentioned in a Wheatstone’s bridge, the deflection of the 
needle followed the direction of the current, and the anticipated loss or gain 
of current was fully realized.” 
Submarine Photography. — M. Bazin illuminates the bottom of the sea by 
means of electric light, for the purpose of discovering the position of 
sunken vessels, &c. His photographic studio consists of a strong iron box, 
braced transversely, and admitting the light through lens-shaped water- 
tight windows ; and he can remain in it without inconvenience for about 
ten minutes. He has, it is said, produced sharp and well-defined photo- 
graphs, suited to render easy the recovery of objects 'sunk to considerable 
depths, and has already worked at depths approaching to 300 feet. — Builder. 
On the Halo o/ , 22§°. — Professor Miller read a paper on this subject before 
the Cambridge Philosophical Society. He commenced by a slight sketch of 
the difficulties which had been experienced in accounting for the pheno- 
menon of haloes, especially in those of 46°. After mentioning some experi- 
ments by himself and Mr. Bravais, which showed that the larger halo was 
best explained by supposing refraction to take place through the terminal 
and one of the lateral faces of the hexagonal prisms of the ice crystal, 
Professor Muller described the results of examining a halo radius of 22^-°, 
which had been seen in Russia to be formed on the ground ; this, and a 
similar halo seen (together with that of 46°) by Professor Ritz during a 
(i tourmente ” in the Kandergrund, proved the present theory, that haloes 
were caused by the refraction of the sun's rays through ice crystals, to be 
right. He also gave an account of some experiments which, during the past 
summer, he had made at Rosenlain, at a height of 4,400 feet, with a polari- 
scope, which showed that the light of a halo was such as is polarized by 
refraction. 
The Physics of a Meteorite . — In a recent note in the Proceedings of the 
Royal Society, the Rev. Samuel Haughton, of Trinity College, Dublin, gives 
a very graphic account of the fall of an aerolite. The fire-ball was seen by 
two peasants, who have given the following written statement of their ob- 
servations ; and since the facts described by these ignorant men correspond 
exactly with the facts theoretically believed to present themselves, we think 
the description of the highest interest. It is headed, The Statement of 
Eye-witnesses, and runs as follows: “I, John Johnson, of the parish 
of Clonoulty near Cashel, County Tipperary, was walking across my potato- 
garden at the back of my house, in company with Michael Ealvy and William 
Furlong, on August 12, 1865, at 7 p.m. when I heard a clap, like the shot 
out of a cannon, very quick and not like thunder ; this was followed by a 
buzzing noise which continued for about a quarter of an hour, when it came 
over our heads, and looking up, we saw an object falling down in a slanting 
direction ; we were frightened at the speed, which was so great that we 
could scarcely notice it ; but after it fell we proceeded to look for it, and 
found it at a distance of forty yards, half-buried in the ground, where it had 
struck the top of a potato-drill. We were some time looking for it (a longer 
time than that during which we had heard the noise.) On taking up the 
