1866.] rr. Astronomy. 79 
means of the eye-piece would still further have enhanced the dis- 
tinctness of view. As the penumbra gradually encroached on the 
disk, it was remarked that the various details of the lunar surface 
came out much more distinctly than when seen under the full and 
direct illumination of the sun; and but for the intention to devote 
the telescope for the time being solely to photography, sume note- 
worthy observations could have been made respecting the con- 
figuration and appearance of lunar objects under the peculiar cir- 
cumstances of an eclipse. Seventeen photographs were procured 
between 7h. and 11h. 5m., this interval of time commencing nearly 
an hour and a half previous to the first contact of the penumbra, 
and concluding 25 minutes after the greatest phase. At the discon- 
tinuance of the observations the night was still bright. 
The photographs of February, 1858, stand in the stereoscopic 
relation to those of October, 1865—<. e. they combine in the stereo- 
scope and produce good stereoscopic pictures of a lunar eclipse. 
Also, to our eyes, two pictures taken at different epochs of the late 
eclipse, when viewed in the stereoscope, while they necessarily show 
the moon as a flat disk, do yet present the shadow as raised or pro- 
truded, giving in fact the impression of a flat picture of the moon 
covered by a glass shade. ‘This impression, however, is not con- 
veyed to all observers. 
Below we give a brief account of the most noteworthy photo- 
graphs which Mr. De la Rue succeeded in taking during the con- 
tinuance of the eclipse. 
Picture No. 5, taken at 8h. 19m. 7s. (exposure one second), 
shows no appearance of the penumbra. The first contact of the 
real penumbra occurred, according to the ‘ Nautical Almanack,’ at 
8h. 25m. 54s.; and he had anticipated the possibility of being 
able to trace some anti-actinic effects beyond its limits; but the ex- 
pectation was not realized. 
Picture No. 6, 8h. 29m. (exposure two seconds), penumbra just 
traceable ; the first contact of the moon with the penumbra oc- 
curred about three minutes before the epoch of this picture. 
Picture No. 9, 9h. 21m. 29s. (exposure two seconds). The 
elliptical projection of the cone of the penumbra well marked, com- 
mencing close to the south pole, and traceable over Malapert, 
Cahous, Short, Moretus, Gruemberger, over the centre of Clavius, 
skirting Longomontanus, over Hainzel, covering Vitello, on the 
border of Mare Humorum, over Vieta and Byrgius, and passing off 
at the 20th parallel of south latitude on the western limb. No 
part of the umbra was then on the moon’s disk, and the whole cen- 
tour of the moon is visible on the photograph. 
Picture No. 10, 9h. 38m. 58s., about 46 seconds after the first 
contact of the umbra (exposure three seconds), the moon’s surface 
is invisible in the photograph toa small extent beyond the boundary 
