IN NATURE of March 11, Mr. H. G. Wayling states that “At Lansdowne House on August 1, 1774, Priestley discovered oxygen”; and a similar statement is made by Sir Philip Hartog in the “Dictionary of National Biography”.

P. J. Hartog, A. N. Meldrum and H. Hartley, J. Chem. Soc., 1933, 896 DOI: 10.1039/JR9330000896

The Director of the School of Oriental Studies has invited me to contribute to this first number of the Bulletin a sketch of the history of the foundation of the School. The present article has only the modest ambition of supplying to the future historian of the School certain references, dates, and facts indispensable for his task.

THE death of M. Berthelot was briefly recorded in the columns of NATURE last week. The writer has been asked, as a former pupil of the great master, to give some account of his life and work.

ALL things considered,1 it seems probable that God, in the beginning, formed matter in solid, massy, hard, impenetrable, moveable particles, of such sizes, figures, and with such other properties, and in such proportion to space, as most conduced to the end for which He formed them; and that these primitive particles, being solids, are incomparably harder than any porous bodies compounded of them; even so very hard as never to wear or break to pieces; no ordinary power being able to divide what God himself made one in the first creation. Histoire de la Philosophie Atomistique. Par Léopold Mabilleau, Professeur de Philosophie à la Faculté des Lettres de Caen. 8vo. Pp. vii + 560. (Paris: Félix Alcan, 1895.)

SINCE the invention of M. Berthelot's extremely elegant and simple apparatus, described in his “Mécanique Chimique,” vol. i. p. 288, the approximate determination of the latent heat of vaporisation of liquids has become comparatively easy. The exact evaluation of the correction due to the heating of the calorimeter from extraneous sources is, however, a matter of considerable difficulty with the original form of apparatus. The correction is necessarily calculated from data supplied by the thermometric observations made previously to, and after, the actual condensation of the liquid has taken place. For this calculation to be as simple and satisfactory as possible, it is essential that during the whole experiment the temperature of the bodies in the immediate neighbourhood of the calorimeter shall remain approximately constant. In M. Berthelot's method of determination this condition is however not strictly fulfilled. For during the “preliminary period,” although the flame is lighted over the calorimeter, the liquid in the flask has not yet begun to boil, so that the radiation to the calorimeter varies, and during the “final period” the flame is extinguished and no further heat reaches the calorimeter from this source. Also during the beginning of the “middle period” a considerable amount of liquid which has been volatilised from the flask at a temperature below its boiling-point, reaches the worm and is there condensed. We therefore modified the apparatus in such a way that the flame was at a constant height and the liquid was boiling during the whole time of the experiment, including both the preliminary and final periods. We found that under these circumstances, with a rise of 3° or 4° in ten minutes, the Regnault-Pfaundler correction is perfectly accurate. We propose shortly to publish a complete description of our apparatus, and shall not therefore go into details at present. It differs mainly from that of M. Berthelot, by the insertion in the interior of the boiling flask of a glass valve, which is opened when the rise of the thermometer in the calorimeter has become steady, and closed when sufficient liquid has been condensed in the worm. The vapour during both the preliminary and final periods passes into a reversed condenser.

IT is well known that the Newlands-Mendeleeff classification of the elements was preceded by the discoveries of certain numerical relations between the atomic weights of allied elements, due to Döbereiner, Dumas, and others; but what has been almost entirely ignored is the immense advance made by M. A. E. Béguyer, de Chancourtois,1 a French geologist of note, Professor at the École des Mines, who was the first to publish a list of all the known elements in the order of their atomic weights.