ovum, but a thin envelope closely investing that membrane, and not appreciable as a distinct structure until the ovum has been crushed. When the chorion first admits of demonstration as a distinct struc- ture the ovum consists of three membranes, a state Mdiich the author has seen in an ovum no farther advanced than about an inch into the Fallopian tube. The chorion subsequently thickens and imbibes a quantity of fluid presenting a gelatinous appearance.
April 25, 1839.
The MARQUIS of NORTHAMPTON, President, in the Chair.
Robert Rigg, Esq. and James Joseph Sylvester, Esq. were balloted for, and dul)^ elected into the Society.
A paper was in part read, entitled, "Account of Experiments on Iron-built Ships, instituted for the purpose of discovering a Correc- tion for the Deviation of the Compass produced by the Iron of Ships." By George Biddell Airy, Esq., M.A., F.R.S., A.R.
May 2, 1839.
The MARQUIS of NORTHAMPTON, President, in the Chair.
Arthur Farre, M.B,, was balloted for, and duly elected into the Society.
A paper was in part read, entitled, " On the Motion of the Blood." By James Carson, M.D., F.R.S.
May 9, 1839.
The MARQUIS of NORTHAMPTON, President, in the Chair.
William Sharpey, M.D. and the Rev. Charles Tumor, M.A. were balloted for, and duly elected into the Society.
The reading of a paper, entitled, "On the Motion of the Blood." By James Carson, M.D., F.R.S., was resumed and concluded.
After referring to his paper contained in the Philosophical Transaction; for 1820, relative to the influence of the elasticity of the lungs as a power contributing to the effectual expansion of the heart, and promoting the motion of the blood in the veins, the author states that his object in this paper is to explain more fully the mode in which these effects are produced, and to corroborate by additional
