397
Instruments :
(c) Equatorial instrument: One equatorial; makers, Alvan Clark &Sons; aperture of objective, inches; magnifying powers of eye-pieces, 93,121,184, 311, 571; negatives, 518,116,230, 335, 375 ; positiveeye-pieces achromatic, 248.
(d) Spectroscope: One by Browning, which consists of 4 whole and 2half prisms of 60° ; flint glass ; gives a dispersive power of ten prismsby reflection.
Chronometer: Sidereal; maker, Victor Kullberg , Loudon.
Riverdale, Heav York.
Private Observatory.
Longitude from Washington,-.
Director : William Meikleham.
Observatory was removed from Fordham, H. Y.
Instruments :
(c) Equatorial instrument: Maker, J oiin Byrne, of Hew York ; ap-erture of objective, 4 t 3 o inches; focal distance, 65 inches; magnifyingpowers of eye pieces, 20, 30, 45, 60, 80, 150, 250, 300, 350, and 450; alsoan amplifier, which doubles each of these powers when used. Attachedto the telescope is a finder of 1J inches aperture, magnifying 20 diame-ters. Right ascension circle divided to read to 4 seconds of time; dec-lination circle divided to read to 1' of arc. Both circles divided onsilver and read by microscopes attached thereto. Driving clock.
(d) Spectroscope : One.
(g) Cloclc: Mean time; maker, Seth Thomas, Sons & (Jo.
(?) Miscellaneous: Filar micrometer; divided on silver to measure0".3 of arc in distance and 6' in position, with suitable eye-pieces andilluminating apparatus.
Rochester, Hew York.
Warner Observatcry.
Longitude from Washington, 3 m 8 3 W.
Authority for longitude and latitude : Signal Service Officer.
Instruments :
(c) Equatorial instrument: Makers, Alvan Clark & Sons (construct-ing) ; aperture of objective, 16 inches; magnifying powers of eye-pieces, from 45 to 2000. (c') Altitude-azimuth, 4J inches, by Fitz;powers from 25 to 432. Telescope 4^-iuch refractor, originally by Fitz,but since last report the flint lens of the objective was unfortunately