Additional Manuscripts a

'Cooke's is in the 5th vol of the Memoirs of the American Academy of Arts and Sciences [Josiah Parsons Cooke, 'The Relation Between the Atomic Weights', 1854] Whether his classification is a great new step you are a better judge than I am - It was new to me when I read it'. JH gives a brief review of Cooke's theory [that elements can be arranged in six series in the manner of organic compounds, and with the atomic weights of each series progressing by integral multiples of an integer unique to that series - Ref. George S. Forbes, DSB, pp. 397-398] and those working in the field. JH would be obliged if WW could send him half a page explaining capillary attraction.