1864. | Physical Science. 741 
Some valuable remarks were made by Professor Phillips on the 
“ Physical Aspect of the Sun.” In this examination he had been much 
aided by Cook’s Solar Eyepiece, by means of which he was enabled to 
observe highly luminous bodies. He wished to draw attention to two 
phenomena—the facule and the porosity; he had observed the former 
as distinctly as the clouds in our own sky. ‘These luminous places 
were shaded as clouds are with us, and as the Alps appeared at some 
50 miles distance. Some of these facule were ranges of 40,000 miles 
long and 40 miles high. With regard to the question of porosity, all that 
he had observed was an irregular mottled surface between the luminous 
bands which he had called facule, but these markings might be com- 
pared to anything, assuming accidental shapes, and formed no definite 
figure. 
On Monday, Dr. Miller, on behalf of himself and Mr. Huggins, 
read a most interesting paper, “On the Spectra of some of the Heavenly 
Bodies.” The paper directed attention to three leading points, viz. 
facts relating to the planetary spectra, others relative to the spectra of 
double stars, and some data concerning the spectra of nebule. The 
presence of metals, as evidenced in the case of the light of the planets 
and some of the heavenly bodies, proved them to be composed of ter- 
restrial substances, whilst the nebule were as evidently bodies of 
gaseous vapour, the character of their light showing that there was 
no solid matter in them. In the discussion which followed the read- 
ing of this paper, Mr. Balfour Stewart said that the remarks on the 
planetary nebula were most important, in showing quite a different 
constitution of these nebule than had been hitherto accepted. 
Mr. A. Claudet read a long and valuable paper, “On Photc- 
_ sculpture,” the invention of M. Willeme, a French sculptor. This 
gentleman saw that if he had photographs of many profiles of his 
sitter taken at the same moment by a number of cameras placed 
around, he might alternately and consecutively correct his model by 
comparing the profile outline of each photograph with the correspond- 
ing outline of the model. But it soon naturally occurred to him that, 
instead of correcting his model when nearly completed, he had better 
work with the pantagraph upon the rough block of clay, and cut it out 
gradually all round by following one after the other the outline of each 
of the photographs. Now, supposing he had twenty-four photographs 
representing the sitter in as many points of view all taken at once, he 
had but to turn the block of clay after every operation 1-24th round, 
and to cut out the next profile, and repeat this until the block had com- 
pleted its entire revolution, and the clay would be transformed into a _ 
perfectly solid figure of the twenty-four photographs,—the statue or the 
bust was made, and only required the finishing touches to be given to it 
by the artist, who would perform the last operation and would exercise 
his skill in communicating to the model all the refinement with which, 
as a sculptor merely, he could have endowed it. Mr. Claudet said, in 
conclusion, that he thought he could not better illustrate the process 
of photosculpture than by executing the bust of the President, Sir 
Charles Lyell. The photographs were taken on the 16th of August ; 
