100 YEARS AGO

The improvement in distance over which it is possible to signal has been very marked. The empirical law put forward by Mr. Marconi that, other things being equal, the distance over which signalling would be possible was proportional to the product of the heights of the masts at the two ends seems to be fairly well established as a working rule. But the improvements in transmitting and receiving apparatus have been so great that it is now possible to signal over much greater distances with the same heights of masts than was the case in 1898. For example, in 1898 Mr. Marconi was only able to cover 15 miles with vertical wires 120 ft. high, whereas to-day, according to the recent announcement made by Prof. Fleming, a distance of 200 miles from the Lizard to St. Catherine's, Isle of Wight, has been signalled over with masts only 160 ft. high... across land such great distances have not been attained, but here again we think the credit of having signalled over the greatest distance must be given to Mr. Marconi, who established in 1899 communication between Dovercourt and Chelmsford, a distance of more than 40 miles.

From Nature 2 May 1901.

50 YEARS AGO

It is in the tradition of British natural history that the only monograph on the water-mites of this country — the Ray Society's three volumes on “The British Hydracarina” — should have been written by two amateur naturalists, C. D. Soar and William Williamson. Williamson, born in Leith in June 1869, was during practically the whole of his working life a clerk, and latterly chief clerk, in the Scottish American Mortgage Company in Edinburgh. His interest in natural history began fortuitously, on account of his discovery, in the course of miscellaneous reading, of a series of articles describing British water-mites which appeared in Science Gossip in 1899 and 1900. The author was C. D. Soar, and Williamson, finding that he could easily identify from the detailed descriptions the water-mites he began to collect, got in touch with Soar, so commencing a friendship which lasted until Soar's death, almost forty years later. The contact was in a way a turning-point in his life, for the enthusiasm of one amateur stimulated the other, and Williamson's spare time now became devoted to collecting, identifying and recording hydrachnids.

From Nature 5 May 1951.