446 CURRENT TOPIG.

India-rubber Production in 1912. S. FIGGIS AND Co. (London.) -In 1912 the world’s supply of rubber was about 92,ooo tons, or, if guayule be included, gg,ooo tons ; in 1911 the production was 88,000 tons. About g5o,ooo acres are producing rubber in the East, and about 80,000 acres in Mexico, Nicaragua, and Honduras. The exports from Erazil, Bolivia, and Peru were 50,720 tons in 1912, against 44,170 tons in 1911; about 1000 tons of guayule were exported from Mexico last year. Exports from Ceylon and India amounted to hgoo tons, from Malaya 22,200 tons, and from the West African Coast about 13,800 tons. Imports of rubber into England were :

I”$P2JJT. De:;;?. Stoc~J~ec. 31.

1910 . . . . . . . . . . . 32,659 29,980 5231 1911 . . . . . . . 33,964 34,054 3954

* 1912 . . . . . . . . . . . 43,853 44,238 3569

Imprts of Pari (Manaos) rubb’er into England were 11,377 tons in 1912, 11,726 in 1911, and 12,433 tons in 1910, and of Peru (Cauchu) 3792 tons in 1912, 3753 tons in 1911, and 5577 tons in 1910. Of East India and Malay plantation rubber 21,211 tons were imported into England in 1912, as compared with 10,656 tons in 1911 and 6598 towns in 1910.

Pebbles Carried by the Wind. ANON. (Sci. Amer., cviii, I, I7.)-It has been shown that a wind with a velocity of 23 metres per second can transport through the air particles of sand not exceed- ing 2 millimetres in diameter. Yet occasionally “ rains of stones ” of much larger size have been obs#e,rved. Thus a fall is recorded in the Canton de Vaud of stones of 1% centimetres in diameter and weighing up to 2.62 grammes. The nearest region whence they could have come was Maures.and Esterel. In ChBteau Landon small calcareous stones of 3 centimetres diameter were carried 150 kilometres. In 1883, in Sweden, stones as large as filberts, enveloped in large ovoid hailstones, and weighing nearly 6 grammes, were carried 60 kilometres. Such cases are discussed by M. Thoulet in Les Annalcs de PIrzstitut OcGanographique, and a plausible expla- nation is suggested. The idea must be accepted of some sort of fixation around the pebbles of an envelope of air or of water vapor. The density of the transported body would then not be that of the pebble but that of the mass of combined solid and fluid (or gaseous) matter, which would be sensibly lighter with respect to its volume.