278 Scientific Intelligence. 
it an eye lens of two inches focal length. The dark disk appeared with 
a trace of faint diffractive fringes round it ; and anumber of streaks or 
trains of ight converging from its edge to its centre, which there crossing 
gave rise to a bright round spot The e appearance ‘of, separate streaks is 
in this one riment, the edge is within the area of the rays, yet a part of 
the same phen omenon (viz., the line of light along the edge) is seen, even 
when the edge is beyond the rays, by the naked eye, or r with a telescope. 
pa s rays reflected from a very small globule of mercury,) and the rays 
re wholly intercepted by the disk at the distance of about two inches, so 
2 ap both the luminous point and the disk may be seen at once in focus 
a small telescope about twelve feet distant, the luminous patch on the 
edge of the disk at the part nearest the luminous point appeared to ex- 
tend to a small distance inwards, and there the rays converging crossed, 
itl 
e experimental imitation of the case of the star. ‘I'he orifice is not 
an absolute point; Dis Mi it were, the patch of light on the disk might 
appear like a projec of its image. Another “explanation has been 
proposed of the plienamehon of projection ; on the principle that, owing 
to aberration, the star being seen out of its true place, a screen , placed 
in its true direction, as the 1 moon, would exhibit the star projected on its 
disk (Astron. Soc. Reports, vi, 246 ); and, taking into account the proper 
oe of the star, this will explain the appearance of the phenomenon in 
ne instance and not in another, on the supposition that those proper mo- 
fie are in opposite directions in the two instances. But this will not apply 
in the very instance to which reference has been made he the two stars 
119 and 120 min »—which have pro ee motions both in the same direc- 
altogether, Sen has been lately suggested by Prof. Challis, on the 
of aberration. The whole snbjec erhaps, not yet ri 
explanation, since the first astronomers variance as to the 
if tru 
seem to point to some ocular cause. Hence, a farther accumulation of 
instances is much wanted : — gee ae which Prof. Powell we tae 
be thankful to receive, a to him, fo 
2 
Maury, Liew. U. S. Navy, during the year 1845, at the U. 5. Naval 
Observatory, ne Vol. i, pablished by authority of the Sec- 
retary of the Navy.—lIn the sini of this Journal for March, 1846, 
. 294, we gave a brief heechgtial of the Naval ee po Wash- 
ington, with a notice of each of the principal instruments. We con- 
cluded that notice with the remark, “ The publie are ciscintelé looking 
for the fruits of this noble establishment. May their reasonable expec: 
tations not be followed by disappointment.” We confess we had at 
> time some misgivings as to the fate of this enterprise. The project 
of a National Observatory had hitherto received so little favor at Wash- 
