Papers read to the Society, February 21, 1901.

I. “An Attempt to Estimate the Vitality of Seeds by an Electrical Method.” By Dr. A. D. Waller, F. R. S. II. “On a New Manometer, and on the Law of the Pressure of Gases between 1.5 and 0.01 Millimetres of Mercury.” By Lord Rayleigh, F. R. S. III. "An Investigation of the Spectra of Flames resulting from Operations in the Opeiishearth and ‘Basic' Bessemer Processes.” By Professor W. N. Hartley, F. R. S., and Hugh Ramage. IV. “The Mineral Constituents of Dust and Soot from various Sources.” By Professor W. N. Hartley, F. R. S., and Hugh Ramage. V. “Notes on the Spark Spectra of Silicon as rendered by Silicates.” By Professor W. N. Hartley, F. R. S. VI “On the Conductivity of Gases under the Becquerel Rays.” By the Hon. R. J. Strutt, M.A., Fellow of Trinity College, Cambridge. Communicated by Lord Rayleigh, F. R. S.