277 
average, it is usually followed by excessive cold between the Decem- 
ber and March following,” by G. V. Vernon, F.R.A.S., M.B.M.S. 
January 12 th, 1864. — “Note on the Amount of Carbonic 
Acid contained in the Air of Manchester,” by Henry E. Roscoe, 
B.A., Ph.D., F.R.S. 
February, 9 th 1864. — “ On the Photochemical Effect of the Light 
emitted by burning Magnesium Wire,” by Henry E. Roscoe, 
B.A., F.R.S. 
February Oth, 1864. — “On the Tensile Strength of Cotton as 
affected by various Chemical Treatments,” by Chas. O’Neill, F.C.S. 
February 23rd, 1864. — “Note on the Preparation of Calcium,” 
by Mr. Edward Sondstadt, communicated by Professor Roscoe. 
February 23rd, 1864. — “ On the Nature of Friction in Me* 
chanics,” by J, C. Dyer, V.P. 
March 8th, 1864. — “On the Existence of the Willow Leaf- 
shaped Bodies on the Sun’s Surface,” by E. J. Stone, M.A., com- 
municated by Mr. James Nasmyth. 
March 8th, 1864. — “On Periodic Changes in the Magnetic Con- 
dition of the Earth, and in the Distribution of Temperature on its 
Surface,” by Jos. Baxendell, F.R.A.S. 
March 2 2nd, 1864. — “ On the Microscopic Structure of the 
Cotton Fibre,” by Captain John Mitchell, of Madras, communicated 
by Mr. Hurst. 
March 2 2nd, 1864. — “Notes on Spinning Machines: Pai't I., 
The Mule Jenny,” by J. C. Dyer, V.P. 
LIBRARIAN’S REPORT. 
Since the close of last Session 396 vols., 216 parts of vols 
of non periodical works, 214 pamphlets, and 27 quarterly, 
1 6 1 monthly and 303 weekly numbers of periodicals, have 
been added to the Library, of which 169 vols., 13 quarterly 
and 35 monthly numbers by purchase; the remainder by 
exchange or donation. 
