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The Pamphlet Collection of Sir Robert Stout: Volume 50

The Telescope

The Telescope.

This cut is taken, by consent of the publishers, Messrs. Harper & Brothers, of [unclear: Ne] from Loomis's Practical Astronomy, a work that has been used as a standard for a [unclear: has] in this Observatory. Comparing the cut with the Equatorial here, one would [unclear: inhc] must have been intended to represent our instrument.

page 51

The Meridian Circle (4) was made by Brunner of Paris. The object glass has a [unclear: dear] aperture of 2 1-16 inches, and a focal length of 23 inches. The circle is 10½ [unclear: aches] in diameter. It is graduated on silver to five minutes, and reads by two [unclear: herders] and microscopes to three seconds. This instrument has five vertical wires and one horizontal. This system of wires may be illuminated by light reflected from [unclear: their] of two silvered mirrors, one of which may be placed in the axis of the [unclear: instrument] the other in front of the object glass. The eye-piece is furnished with a [unclear: rejecting] prism, and with sun-shades. There are two spirit levels belonging to this [unclear: Instrument], one of which is attached to the circle, the other a striding level to be [unclear: based] on the axis. The usefulness of this instrument has been greatly increased by [unclear: the] addition of a filar micrometer, made by W. T. Gregg, of New York.

The Alt-azimuth Instrument. (7) was made by E. & G. W. Blunt, of New York, The object glass has a clear aperture of 2 1/8 inches, and a focal length of 22 inches. The circles are 12 inches in diameter, and graduated to 10 minutes. The horizontal circles has four verniers with microscopes, and the vertical circle two; and each reads to ten seconds. This instrument is furnished with direct and reflecting eye-pieces, a collimating eye-piece and sunshades. The system of wires and the arrangement of the levels are the same as in the transit instrument. The illumination of the wires is effected by means of a silvered mirror placed in the axis.

In the old observatory this instrument was mounted under an opening in the roof which allowed motion only in or near the meridian. It is now mounted under the dome at the west end of the new building. In this position it can be directed to any point above the horizon, and thus be made more serviceable than it could be in its old position.

The Transit Theodolite (3) was made by Gregg & Rupp, of New York. The [unclear: object] glass has an aperture of 1? inches, and a focal length of 18 inches. The [unclear: horizontal] circle is 10½ inches in diameter, and reads by a vernier to one-half a minute; [unclear: the] vertical circle is 8 inches in diameter, and reads to one minute. The magnetic [unclear: needle] carries a vernier at each end, by means of which the are of the compass box can be read to single minutes. This instrument has two wires, illuminated in the same way as in the altitude and azimuth instrument. Belonging to this instrument is a strong portable tripod used for field work.

The Sextant was made by E. & G. W. Blunt, of New York. The are is [unclear: graduated] on silver, and reads by a vernier and microscope to ten seconds.

The Sidereal Clock (5), which was made by Gregg & Rupp, of New York, has a mercurial pendulum.:

The Solar Clock (6) was made by Riggs, of Philadelphia.

The sidereal clock stands upon an isolated brick pier in the southwest corner of the transit room. The solar clock hangs on the pier which supports the alt-azimuth instrument.

The Observatory is connected by a loop with the lines of the Western Union Telegraph Company, thus furnishing the means for illustrating the method of finding the longitude by electric signals.

The present greatly improved condition of the observatory is due to the liberal-By of the President, Dr. S. S. Laws, who, for the advancement of astronomical science, has given to the University more than two thousand dollars in order to procure the Telescope and put it in complete working order, and to move and enlarge the Observatory Building.

page 52

In view of this liberalty on the part of Dr. Laws, the Board of Curators is decided that the Observatory shall hereafter be known as "The Laws [unclear: Obsertort]," and the Telescope as "The Laws Telescope." They have also [unclear: established] a prize in the form of a gold medal, to be known as "The S. S. Lawrytronomical Medal," to be awarded annually to that student who shall stand [unclear: highest] in Theoretical and Practical Astronomy.