INTERNATIONAL ATOMIC WEIGHTS. 1001 International Atomic Weights. THE Council has ordered the follo,wing letter and Table t o be printed in the Journal of the Society: WHINFIELD, SALCOMBE, S. DEVON. October l s t 1917. DEAR SIRS, I beg to inform you that the International Atomic Weight Committee have decided t o intermit their Annual Reports owing primarily to the fact that certain of its members a10 largely occupied with matters arising out of the War and that it has been found difficult owing to the interruption of communications to keep in correspondence. Furthermore-and this is the more important circumstance-practically all experimental work on the subject of Atomic Weights is for the time being interrupted; indeed with the entrance of the United States of America into the War i t may be said to be for the present wholly a t an end, and no memoir of importance has made its appearance since the issue of the last Report.As no change has been shown to be required in the Table last published it is suggested that it should be reprinted as i t stands and regarded as current for 1918. I am GENTLEMEN, Your obedient Servant, T. E. THORPE. The Hon. Secretaries, The Chemical Society, Burlington House, London W 1002 ~ INTERNATIONAL ATOMIC WEIGHTS. Oxygen ........................ o Palladium ..................... Pd Phosphorus .................. P Platinum ..................... Pt Potassium ..................... 11 Praseodymium ............... Pr Radium ........................ Ra Rhodium .....................Rh Rubidium ..................... Rb Ruthenium .................. Ru Samarium .................... Sa Scandium ..................... Sc Selenium ..................... Se Silicon ........................ Si Sodium ........................ Na Strontium .................. Sr Sulphur ..................... S Tantalum .................. Ta Tellurium ..................... Te Terbium ..................... Tb Thallium .................... T1 Thorium ..................... Th Thulium ..................... Tm Tin ........................... Sn Titanium ..................... Ti Tungsten ..................... W Uranium ..................... U Vanadium .................. V Xenon ........................ Xe Ytterbium (Neoytterbium) Yb Yttrium .....................Yt Zinc ........................... Zn Zirconium ..................... Zr ........................ Silver Ag 1918 . Znt ernatio nal A tomic IV eigh ts . Symbol . Aluminium ................. A1 Antimony ..................... Sb Argon ....................... A Arsenic ..................... As Barium ........................ Ba Bismuth ..................... Bi Boron ........................ E Bromine ..................... Br Cadmium ..................... Cd Caesium ....................... Cs Calcium ..................... Ca Carbon ........................ C Cerium ........................ Ce Chlorine ..................... C1 Chromium .................. Cr C'obal t ....................... Co Columbium .................Cb Copper ........................ Cu Erbium ..................... Er Europium ..................... Eu Fluorine ..................... F Gadolinium .................. Gd Gallium .................... Ga Germanium .................. Ge Glucinum ..................... G1 Gold ........................... Au Helium ........................ He Holmium ..................... Ho Hydrogen ..................... H Indium ....................... In Iodine ........................ I Iridium ......................... Ir Iron ........................... Fe Krypton ..................... Kr Lanthanum .................. La Lead .......................... Pb Lithium ..................... Li Lutecium ................... Lu Mangaaneae .................. Mn ................. Dysprosium DY .................. Magnesium Mg Mercury Hg ..................... Atomic weight . 27 *1 120.2 39-88 74*96 137'37 208'0 11.0 79.92 112'40 132.81 40.07 12.005 140'25 35.46 52.0 58.97 93'1 63.57 162.5 167-7 152.0 19.0 157.3 69.9 72.5 9'1 197.2 4-00 163'5 1 '008 114.8 126.92 193.1 55-*84 82.92 139-0 207'20 6 '94 175.0 24-32 54'93 200'6 Atomic weight . 96. 0 144 *3 20.2 58.68 262.4 14-01 190 -9 16'00 106.7 31.04 195.2 39'10 140.9 226 *O 102 '9 101-7 150-4 44'1 79.2 28.3 107'88 23'00 87-63 32.06 85.46 181.5 127.5 159.2 204.0 232'4 168.5 118'7 48-1 184-0 238'2 51'0 1 * 2 SD 173'5 88.7 65*37 90-