MarcH 29, 1912] 
oxide (K,O) in solution. The average salin- 
ity of the brine is 43.82 grams of solids per 
one hundred cubic centimeters. Comparison 
of the results indicates that the brines are 
nearly uniform throughout the flat. The prob- 
able importance of the deposits is due to the 
occurrence of the potassium salts in soluble 
form in a natural saturated brine, and under 
climatic and other conditions especially 
favorable to its separation and recovery by 
solar evaporation. Existing data give reason- 
able assurance that the brine-saturated salt 
body is at least 60 feet thick and covers an 
area of at least eleven square miles. Assum- 
ing the salt body to contain twenty-five per 
cent. by volume of the brine, the total amount 
of potassium oxide is estimated at over four 
million short tons. This estimate is believed 
to be very conservative, and the available ton- 
nage may well be expected to exceed ten mil- 
lion tons, which would supply the country, at 
the’ present rate of consumption of potash, for 
thirty years. At any rate it appears that this 
locality constitutes a very important source of 
potash in probably readily available commer- 
cial form. 
As a result of the recommendations recently 
made by a joint committee of the South 
African Association for the Advancement of 
Science and the Royal Society of South 
Africa, a general committee, says Nature 
quoting from The South African Journal of 
Science, has been constituted for the purpose 
of considering applications received for grants. 
Five grants, amounting in all to £250, were 
made at the first meeting of the committee 
held towards the end of last year. The grants 
were: (1) £40 to Professor W. A. D. Rudge, 
of Grey University College, Bloemfontein, to 
obtain a continuous record of the variations 
in the atmospheric gradient at various places, 
and to ascertain the relation between potential 
gradient and altitude, and between the diurnal 
variation of the gradient and the variation 
in the atmospheric pressure; (2) £45 to Pro- 
fessor A. Young, of the South African Col- 
lege, Cape Town, to investigate the occurrence 
of semi-diurnal, diurnal and spring and neap 
SCIENCE 
493 
tides observed in connection with an artesian 
well in the Cradock district; (3) £75 to Miss 
D. F. Bleek, to proceed to the Kalahari, so as 
to obtain phonographic records of the spoken 
language of the Bushman tribes north of the 
Orange and Vaal rivers; (4) £50 to Mr. R. 
N. Hall, to visit localities in Rhodesia, where 
Bushman paintings exist; (5) £40 to Mr. W. 
T. Saxton, of the South African College, 
Cape Town, for the purpose of studying the 
fungus diseases of trees in the Transkeian 
forests, investigating the ecology of the typi- 
cal formations of the Transkeian territory, in- 
vestigating a reported occurrence of the typi- 
cal western province flora at St. John’s, and 
to collect material for the study of the two 
genera of South African cycads, Stangeria 
and Hncephalartos. 
Dr. G. D. THomson, of Canton, writes the 
Geographical Journal an account of some 
caves in the south of the Kwang-tung prov- 
ince, which, he says, have never yet been de- 
scribed by a European traveler. They lie 
about 250 miles southwest of Canton, by the 
route followed by boat. This involves the de- 
scent of the Canton River to the sea, and a 
coasting voyage west to the mouth of the 
Yeung-Kong River, which is ascended to the 
city of the same name. Here it is necessary 
to change boats, taking a native craft, pulled 
or poled by native men and women when the 
wind is contrary. In this way the walled city 
of Yeung-chou is reached, and the caves are 
situated a mile or more to the west of it. The 
chief cave is of large size and very beautiful. 
The hills in the immediate neighborhood rise 
abruptly from the plain in jagged rocky cliffs 
of totally different formation from the sur- 
rounding hills and mountains. At the en- 
trance and on ledges high up the cliff there is 
a Buddhist monastery and shrines, presenting 
a gaudy appearance. From the outer cham- 
ber, which is beautified with stalactites and 
stalagmites, a flight of steps leads up to a sec- 
ond, cathedral-like cavern, not visible from 
the first. In this there is a stone table and 
stools, and shrines around the walls in niches, 
but the whole upper part is untouched by 
