FEU ae ee 
Miscellanies. 225 
comprehensible nature and origin of the light of the great nebula of 
Orion; will it give us in easily appreciable quantity the parallax of some - 
of the fixed stars, or will it make sensible to us the parallax of the neb- 
ule themselves; finally, having presented to us original portraits of the 
moon and of the sidereal heavens, suchas man has never dared even to 
anticipate, will it by daguerreotypic aid administer to us copies founded 
upon truth, and enable astronomers of future ages to compare the moon 
and heavens as they then may be, with the moon and heavens as they 
were? Some of these questions will be answered affirmatively, others 
negatively, and that, too, very shortly ; for the noble maker of the 
noblest instrument ever formed by man ‘has cast his bread upon the 
waters, and will, with God’s blessing, find it before many days.’ ” 
“¢ As it is interesting to trace the progress of human industry and in- 
telligence, I will say afew words, indicating their effects as far as con- 
cerns the Newtonian reflecting telescope. It was discovered by the 
head and made by the hands of Sir Isaac Newton in 1671; its large 
speculum was two inches and three tenths in diameter ; its focal length 
was about 6 inches, and magnified 38 times; it is in the possession of 
the Royal Society. I regret to say it is ina most dilapidated condition, 
and its eye-glass is lost. 
“The next of any importance was made by Hadley in 1723; its large 
speculum’s diameter was about 6 inches; its foal length about 63 in- 
ches; it magnified 230 times; in performance it equalled the great 
Huygherian refracting telescope, of 6 inches diameter and 123 feet focus. 
He gave it to the Royal Society. Its metal is ruined, and its tube, its 
stand, and others of its appurtenances are lost. 
“Short succeeded Hadley. The figure of his metals was very good, 
but their composition was bad and very liable to tarnish. Siill he 
greatly excelled all who had gone before him, and, that posterity might 
not be aided in their attempts to make reflecting telescopes by any 
knowledge he had acquired, he ordered, before his death, all his tools 
to be destroyed. 
“‘ Next to Short came Herschel ; his metals were of a very inferior 
composition; in others’ hands his telescopes did but litile, but in his 
own they raised for him an imperishable name. 
** Watson followed Herschel. His metals,in composition, figure and 
polish, were exquisitely perfect; his largest Newtonian did not exceed 
9 inches aperture; with large ones he never grappled, but for such as 
he did make I doubt if he was ever equalled, and am sure he never 
was surpassed. 
“Cotemporary with Watson was Tulley ; his telescopes were superior 
to Short’s, but certainly inferior to Watson’s. 
Vol. xz1x, No. 1.—April-June, 1845. 29 
