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On Fibre. Additional Observations. By Martin Barry, M.D. F.R.S.
Barometrical Observations, showing the effect of the Direction of the
On the Rectification and Quadrature of the Spherical Ellipse. By
On the Transparency of the Atmosphere, and the Law of Extinction of the Solar Rays in passing through it. By James D. Forbes, Esq. F.R.S. &c.
On the Specific Inductive Capacities of certain Electric Substances.
On the Action of the Rays of the Solar Spectrum on Vegetable Colours. By Sir John Frederick William Herschel, Bart. K.H. F.R.S. Experimental Researches on the Elliptic Polarization of Light. By the Rev. Baden Powell, M.A. F.R.S. Savilian Professor of Geometry in the University of Oxford
On the Influence of the Moon on the Atmospheric Pressure, as deduced from the Observations of the Barometer made at the Magnetic Observatory at St. Helena. By Lieut. J. H. Lefroy, R.A. late Director of that Observatory
Notices of the Aurora Australis from the 1st to the 31st of March 1841, made on board H.M.S. Erebus; extracted from the log-book. By Capt. James Clark Ross, R.N. F.R.S.
An Appendix to a paper on the Nervous Ganglia of the Uterus, with
396 Magnetic and Meteorological Observations for February 1842, taken at the Magnetic Observatory at Madras. Presented by the Honourable Court of Directors of the East India Company Magnetic and Meteorological Observations from May 1841 to March 1842, made at the Observatory established by the Rajah of Travancore, at Trevandrum, transmitted to the Royal Society by command of His Highness the Rajah. By John Caldecott, Esq. F.R.S. Director of the Observatory at Trevandrum.........
Postscript to a paper On the Action of the Rays of the Solar Spectrum on Vegetable Colours.' By Sir John Frederick William Herschel Bart. F.R.S. &c.
Observations de la variation de la déclinaison et intensité horizontale magnétiques observées à Milan pendant vingt-quatre heures consécutives, le 22 et 23 Juin, le 20 et 21 Juillet, le 26 et 27 d'Aout, le 21 et 22 Septembre, et le 19 et 20 Octobre, 1842, rapportées par Robert Strambrecchi, premier élève adjoint....................... 398 On certain improvements on Photographic Processes described in a
former communication. By Sir John Frederick William Herschel, Bart. K.H. F.R.S. &c., in a letter to Samuel Hunter Christie, Esq. Sec. R.S......
Boring Register, Bow Island, South Pacific. By Captain Edward
Experimental Inquiry into the cause of the Ascent and Continued Motion of the Sap; with a new method of preparing plants for physiological investigations. By George Rainey, Esq. M.R.C.S... 432
On the Nerves. By James Stark, M.D...................................
A Letter from Prof. Hanson to G. B. Airy, Esq. F.R.S. A.R. On a New Method of computing the Perturbations of the Planets whose eccentricities and inclinations are not small.'.......
Variation de la Déclinaison et Intensité Horizontale observées à Milan pendant vingt-quat erheurs consécutivese le 25 et 26 Novembre, et le 21 et 22 Décembre 1842. Par Prof. Carlini, For. Memb. R.S... 435 On the minute structure of the Skeletons or hard parts of Invertebrata. By W. B. Carpenter, M.D...............................
Observations on certain cases of Elliptic Polarization of Light by Reflection, By the Rev. Baden Powell, M.A. F.R.S. Savilian Professor of Geometry in the University of Oxford
Variation of the Magnetic Needle as observed at Washington City,
On the Structure and Mode of Action of the Iris. By C. R. Hall,
Tide-Observations at Tahiti. By Captain Edward Belcher, R.N...... 440
Researches on the Decomposition and Disintegration of Phosphatic Vesical Calculi; and on the introduction of Chemical decomponents into the living Bladder. By S. Elliott Hoskins, M.D.
A Method of proving the three leading properties of the Ellipse and
On the Laws of Individual Tides at Southampton and at Ipswich. By
On the import and office of the Lymphatic Vessels. By Robert Willis,
Further Observations on the descending fluids of Plants, and more
P. 386, line 9, for "the filaments of which are," read "this filament is."
FRANCIS BAILY, Esq., V.P. and Treasurer, in the Chair,
"Description of a new Barometer, recently fixed up in the Apartments of the Royal Society; with remarks on the mode hitherto pursued at various periods, and an account of that which is now adopted, for correcting the observed height of the mercury in the Society's Barometers.' By Francis Baily, Esq., Vice-President and Treasurer, R.S.
The barometer, here alluded to, may in some measure be considered as two separate and independent barometers, inasmuch as it is formed of two distinct tubes dipping into one and the same cistern of mercury. One of these tubes is made of flint glass, and the other of crown glass, with a view to ascertain whether, at the end of any given period, the one may have had any greater chemical effect on the mercury than the other, and thus affected the results. A brass rod, to which the scale is attached, passes through the framework, between the two tubes, and is thus common to both: one end of which is furnished with a fine agate point, which, by means of a rack and pinion moving the whole rod, may be brought just to touch the surface of the mercury in the cistern, the slightest contact with which is immediately discernible; and the other end of which bears the usual scale of inches, tenths, &c.; and there is a separate vernier for each tube. A small thermometer, the bulb of which dips into the mercury in the cistern, is inserted at the bottom : and an eyepiece is also there fixed, so that the agate point can be viewed with more distinctness and accuracy. The whole instrument is made to turn round in azimuth, in order to verify the perpendicularity of the tubes and the scale.
It is evident that there are many advantages attending this mode of construction, which are not to be found in the barometers as usually formed for general use in this country. The absolute heights are more correctly and more satisfactorily determined; and the permanency of true action is more effectually noticed and secured. For, every part is under the inspection and control of the observer; and any derangement or imperfection in either of the tubes is immediately detected on comparison with the other. And, considering the care that has been taken in filling the tubes, and setting off the