100 YEARS AGO

Prof. F. P. Venable briefly discussed the nature of the elements in his address to the Section of Chemistry. He passed in review some of the evidence which leads to the belief that the so-called elementary atoms are but compounds of an intimate peculiar nature, the dissociation of which has not yet been accomplished. Referring to the conclusions to which investigations lead, it was remarked that the hypothesis that the elements are built up of two or more common constituents has a larger number of supporters, and would seem more plausible than Graham's hypothesis. Some have supposed one such primal element by the condensation or polymerisation of which the others were formed. Others have adopted the supposition of two elements. There are many practical difficulties in the way of these suppositions; the lack of uniformity in the differences between the atomic weights, the sudden change of electro-chemical character, and the impossibility, so far, of discovering any law underlying the gradation in the properties of the elements with the increase of atomic weights, are some of the difficulties. ... It is possible to think of valency as dependent upon the character of the motion of the atom, but one cannot well conceive of a similar dependence of atomic weight and all the other properties.

From Nature 21 September 1899.

50 YEARS AGO

In his presidential address to Section D (Zoology) of the British Association at Newcastle recently, Prof. A. C. Hardy put forward the tentative suggestion that one factor in moulding patterns of behaviour among the members of a given species might be something akin to what is usually called telepathy, a phenomenon which he considered had now been established and which was clearly a revolutionary discovery from whatever point of view it might be regarded. Although, perhaps, a little apologetic in advancing this idea, Prof. Hardy did not conceal his belief that few could reject the evidence for telepathy were they to examine it with unbiased minds and without undue prejudice. ... The study of such matters has, as he rightly pointed out, become a highly specialized and difficult pursuit which the ordinary scientific man cannot hope to follow while at the same time pursuing his own interests and investigations.

From Nature 24 September 1949.