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work of Maxwell and on the experimental work of Hertz. This tribute to the latter was not relished by Ludwig Boltzmann, who rose and took exception to parts of the address, it seems that the physicists of Germany were not too well acquainted with the fundanlental work of Maxwell and that Hertz wrote to Sir ()liver Lodge " referring to the difficulty which he had in getting his results understood by the orthodox professors of his own country; always excepting his quondam chiei, yon Helmholtz."
By a Branly iron-filing coherer the lecturer showed various properties of electric waves. Signals in the Morse code were received from another room, from which they were sent by a telegraphic key controlling the current in an induction coil that operated a Hertz vibrator. The author's confession is interesting: " I had hopes that by the use of short waves, signalling across considerable distances of space could by this means be accomplished:; and the late I.ord Rayleigh urged me to take this matter up and develop it. I did not follow his advice, being fully occupied in teaching, and I had not the perceptive faculty shown about the same time by Sir William Crookes, who anticipated that such a method of telegraphy would be or might become of international importance.
๐ SIMILAR VOLUMES
In each test a series of pans containing known numbers of larvae were distributed over the area to be dusted. Counting the living larvte after dusting furnished a check on the effectiveness of the application. Two final-tests gave particularly clear-cut results, and for this reason were of special
## 822 CURRENT TOPICS. [J. F. I. results are confirmed at different places, then all our theories go into the melting-pot, relativity and all, and a patient resurvey must commence to unravel afresh order from chaos. The only grave mistake we can make at present is to treat Miller's results other