'The Transactions of the Bombay Geographical Society. From January 1863 to December 1864. (Edited by the Secretary.) Volume XVII.' [‎107] (136/524)

BOMBAY GEOGRAPHICAL SOCIETY. cvii
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first to the last volume. It was not of much consequence when once
the explanation was suspected, but it might puzzle one at first to un
derstand why three successive horary readings of the Bombay instru
ment gave 16*28, 16-33, and 16*37, whilst in another Observatory we
meet with such readings as 508*6, 509*0, and 509*7,—the differences
being so very much less in the one case than in the other. In conclu
sion he begged to express the hope that Mr. Broun would find it conve
nient to add to the favour he had already conferred on the Society, by
favouring them as opportunity afforded with other papers of a like kind.
Dr. Sinclair observed that Mr. Broun had laid the Society under
deep obligations by sending to them his valuable papers, in which he
discussed some of the more salient peculiarities of the observations
made in the Bombay Magnetical Observatory, and expressed a hope
that they would be given to the press in anticipation of their publica
tion in the Transactions of the Society, that the information they
contained, and the points raised in them, might be made known as
widely and as early as possible. Dr. Sinclair further stated, that he
thought it a matter of regret that a greater number of copies of the
Bombay Magnetical and Meteorological Observations had not been dis
tributed. Mr. Broun had observed, in reference to the values of the tem
per at u re - c o- e fhcient obtained by his method and by the older method,
that the values generally differed, and differed with the instruments em
ployed, with a single exception —Dr. Lloyd had informed him, that in
the case of the bijilar belonging to the Dublin University Magnetical
Observatory, the difference was found to be nothing. This peculiarity of
the instrument under Dr. Lloyd deserved particular attention. Of the
three illustrious men, Gauss, Lloyd, and Sabine, to whom the world
was so much indebted for the great system of magnetical observations,
which was steadily advancing the knowledge and theory of terrestrial
magnetism, it was to Dr. Lloyd that the designing of the instrument
(chiefly modifications of the ones planned by Gauss) was entrusted ; and
the Observatories in various parts of the world—at Toronto, St. Helena,
the Cape, Van Dieman’s Land, Simla, Madras, and Bombay, were pro
vided with instruments precisely similar to those of the Observatory
under Dr. Lloyd, by whom the first directors of these Observatories were
taught in Dublin the methods of observation. Possibly it might be
to some mode of suspending the Dublin bifilar that the peculiarity
mentioned in Mr. Broun’s paper is to be attributed. Dr. Sinclair