February 5, 1920] 



NATURE 



607 



of at least an inch being- 130. The wettest day 

 at Greenwich in seventy-eight years was July 2'], 

 1867, with 3'67 in., and the number of daily falls 

 of at least an inch was 113. 



A much more interesting comparison, however, 

 is afforded by the tables relating to Adelaide in the 

 south and to Port Darwin in the north. Darwin 

 is 11° within the Tropics and Adelaide 11° out- 

 side, but while Darwin is on the coast, Adelaide is 

 six miles from the nearest point of the sea. The 

 mean height of the barometer, corrected to sea- 

 level, is 0225 in. (or nearly 8 millibars) higher at 

 Adelaide than at Darwin, the extreme readings 

 being at .\delaide 29"204 in. and ya'joif in., and at 

 Darwin 29'oi7 in. and 30' 151 in. The tempera- 

 ture contrasts are striking. The mean tempera- 

 ture at Darwin is 82'7° F., with a monthly mean 

 daily range of i6'8°, and at Adelaide 63'o° F., with 

 a mean range of 197°. Darwin, being a tropical 

 station, has a range of only 8° F., or rather less, 

 between the warmest and coldest months. Ade- 

 laide, on the other hand, has a corresponding 

 range of 22^°. Again, the highest temperatures 

 recorded at Adelaide were ii6"3° in the shade 

 and i8o'o° in the sun; at Darwin, io4'9° in the 

 shade and i68"5° in the sun. It is therefore not 

 surprising to find that readings of at least 100° 

 in the shade occur much oftener at Adelaide — 13'5 

 per annum, as against i"6 per annum at Darwin. 

 It is otherwise with readings of at least 90° in 

 the shade, where the annual numbers are 43*6 at 

 Adelaide, and 237, or nearly two days ■ out of 

 three, at Darwin. The lowest reading at Darwin 

 was 5S'8°, and at Adelaide 32-0°, for air tempera- 

 ture. Terrestrial radiation readings are not given 

 for Darwin, but a minimum of 229° occurred at 

 Adelaide. Darwin also seems to be unprovided 

 with a sunshine recorder, but al Adelaide the 

 annual average is 253i"5 hours, a maximum of 

 28299 hours having been measured in 1898, in 

 which year also the sunniest month occurred, 374 

 hours being recorded in January. 



Many other matters besides rainfall are included 

 in the main part of the volume, as indicated in the 

 following list of tabulations : aurora, bush fires, 

 drought, earthquakes, floods, fog-bows, frost, 

 hail, heat waves, high tides, meteors, mirages, 

 mock moon, plagues and pests and live-stock 

 diseases, heavy rainfall, thunder and lightning, 

 volcanic dust-clouds, water-spouts, hurricanes, 

 cyclones, heavv gales, dust-storms, etc. 



W. W. B. 



NOTES. 



With the assistance of the Air Ministry and the 

 co-operation of Messrs. Vickers, Ltd., Lord North- 

 cliffe has been able to arrange, on behalf of the 

 Times, for an attempted flight from Cairo to Capt' 

 Town, a distance of more than five thousand miles. 

 This journey from one end of the continent of .Africa 

 to the other, and traversing country the nature of 

 a large part of which is little known, is of particular 

 interest to the .scientific world in view of the fact that 

 Dr. P. Chalmers Mitchell, secretary of the Zoological 

 NO. 2623, VOL. 104] 



Society of London, is taking part in it as passenger 

 and observer. The enterprise will thus not only test 

 the practicability of the air route from Cairo to the 

 Cape, but also doubtless lead to valuable scientific 

 observations being made during the flight. The aero- 

 plane left England on January 24 and arrived in 

 Cairo on February 3. The machine is a Vickers- 

 Viniy commercial aeroplane similar to those used for 

 the flights across the Atlantic and to Australia, and 

 it carries a crew of four in addition to the passenger. 

 Dr. Chalmers Mitchell is carrying an autograph letter 

 from the King to Lord Buxton, Governor-General of 

 South Africa, and we hope that he will be able to 

 deliver it in twelve days or so after- a successful end 

 to what is a pioneer effort in scientific exploration 

 from the air. 



The Kew Bulletin (19 19, p. 399) records the appoint- 

 ment by the Government of South .\frica of an 

 Advisory Committee to carry out and supervise a 

 Botanical Survey of the territories included in the 

 Union. Dr. J. B. Pole-Evans, chief of the Division 

 of Botany in the Department of Agriculture, will act 

 :is Director of the Survey, and he will be assisted by 

 a small committee, including several prominent South 

 .\frican botanists and representatives of Government 

 Departments interested. The objects of the survey 

 are to continue and extend the work of the Division 

 of Botany on the systematic study of the vegetation 

 of the country and of the plant parasites of the in- 

 digenous vegetation ; that of the Division of Veterinary 

 Research on the relation of the vegetation to stock 

 diseases ; and that of the Forestry Department on the 

 composition of the indigenous forests, the value of 

 their products, and their industrial possibilities. Also 

 to studv the vegetation from the various points of 

 view of industry, agriculture, and pastoral develop- 

 ment ; to study plant distribution and the influence 

 of South African conditions on the structure and 

 phvsiologv of the native plants ; and to compare and 

 correlate the South African flora and its associated 

 animal and plant diseases with those existing in other 

 parts of the world under somewhat similar conditions. 

 For the purpose of the survey the country will be 

 divided into a convenient number of areas each under 

 the- control of a botanist, and a qualified assistant 

 has been appointed at Kew to aid in the critical 

 examination of the plants collected. 



By a melancholy coincidence the announcement of 

 the appointment by the Egyptian Government of an 

 International Commission to consider the proposals 

 for the extension of irrigation works in Egypt and the 

 .Sudan is followed bv the news from Bombay of the 

 death of Sir Michael Nethersole, who had been selected 

 for the chairmanship of the Commission, but had 

 felt impelled to decline the offer by reason of the 

 claims of his work in India. Born in 1859, Sir 

 Michael passed in 1880 from the Royal Indian En- 

 gineering College at Coopers Hill into the Public 

 Works Department, and, rising through the grade of 

 executive engineer, he became in 1900 Chief Engineer 

 and Secretary to Government in the United Provinces. 

 In this position he remained for a dozen years untiJ 



