422
Instruments:
(«) Meridian circles: 1. Transit circle by Trougiiton & Simms; onemovable and one fixed circle; diameter 36 inches,divided to 5"; 16microscopes (carried by 2 Alidade circles, 1 movable and 1 fixed), read-ing to P'-tenth by estimation; aperture of object-glass 8.59 inches;6i-inch collimators ;'2|-incli axle telescope. 2. Reversing transit withY’s for meridian and prime vertical, by T. Cooke & Sons ; 4-incli ob-ject-glass. 3. Transit instrument by Troughton & Simms ; 2|-iuchobject-glass.
(b) Meridian transit instruments: 1. Alt-azimuth, by Trougiiton &Simms ; 12-inch circles, divided to 5'; 4 microscopes, vertical and hori-zontal circles reading seconds and tenths by estimation. Horizontalcircle movable. 2. Theodolite by T. Cooke & Sons. 3. Theodolite byApps.
(c) Equatorial instruments: One 15.06-inch refractor by Grubb. Sev-eral sets of eye-pieces. Bifilar micrometer. Merz helioscope. Dawessolar eye-piece, 2, 3, 74-inch finders. This telescope is controlled abso-lutely by the sidereal clock. Driving-clock by T. Cooke & Sons, madeto special design. 2. One 12.9-inch reflector 122.5 focus; mirror byRev. H. Cooper Key, English mounting. 3. One 12,j-inch reflector byBrowning. Solar spectroscope. 4. One 6.06-inch refractor by Simms;bifilar and double image micrometers, used generally for comet seeking.5. One 6.04-inch refractor by T. Cooke & Sons ; complete. 6. One4-inch refractor by T. Cooke & Sons; bifilar micrometer. Clock byEichens ; complete. 7. One 3-inch refractor by T. Cooke & Sons.Bifilar micrometer; complete.
(d) Spectroscopes: Large solar spectroscope with 1 whole and 2 halfRutiierfurd prisms,"with reversion and heliometer viewing telescope.Stellar spectroscope modified at Dun Echt (the one most used). Brown-ing 5-prism automatic solar spectroscope and 2 stellar ones; also Vogelspectroscope by Heustrell, and a variety of direct vision, quartz, andother prisms. Besides the above-mentioned spectroscope there is a6-prism automatic reversing-table instrument by Browning, and a handdirect-vision spectroscope used for aurora:.
(e) Photometer ; Zollner astro-photometer by Ausfeld of Gotha.
(/) Chronographs: 1. Four-fold barrel-chronograph, each barrel to run
six hours, driven by the same clock as the 15.06-incli equatorial. 2.Portable fillet chronograph by Siemens.
(g) Cloclcs: 1. Sidereal clock, quicksilver compensation by Frodsham.2. Mean-time clock, quicksilver compensation by Molyneux. 3. Elec-tric clock, outside dial and time gun.
(h) Chronometers: 1. Kullberg; meantime. 2. Farquhar; meantime. 3. J. Walker; mean time. 4. Erodsiiam; mean time 8-day.5. Walker; sidereal (electric contact). 6. Walker; sidereal. 7.McLennan; - 1 4 0 - seconds; pocket M. T.
(i) Miscellaneous: 1. Metre: A copy of the Metre dn Gonservatoire.