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NA 1 URE 



[March i8, 1909 



are the " British Centipedes and Millipedes," by Mr. 

 "Wilfred Mark Webb; the "British Parasitic Copepoda," 

 by Dr. Thomas Scott and Mr. Andrew Scott; the " British 

 H.vdrachnidse, " by Mr. C. D. Soar and Mr. W. William- 

 <;on ; the "British Ixodoidea," by Mr. \V. F. Cooper and 

 Mr. L. E. Robinson; and the " Earwigs of the World," 

 by Mr. Malcolm Burr. The only new botanical work 

 promised is one on the "British Characea;," by Messrs. 

 Henry and James Groves. Lord Avebury, F.R.S., has been 

 re-elected president of the society, Mr. DuCane Godman, 

 F.R.S., treasurer, and Mr. John Hopkinson, secretary. 



The commemoration of the jubilee of the discovery of 

 the source of the White Nile was celebrated by a meeting 

 of the Royal Geographical Society, at which a paper was 

 read by Sir W. Garstin, published in the February number 

 of the journal of the society, entitled " Fifty Years of Nile 

 Exploration, and some of its Results." The. paper begins 

 with a good summary of exploration prior to 1898, when 

 the power of the Khalifa was overthrown and the Sudan 

 re-conquered by the Anglo-Egyptian forces. An account, is 

 given of the hydrography of the river, and of the measures 

 taken in recent years to develop its water supplies for the 

 irrigation of the Delta. There is also a lucid account of 

 the functions in this respect of the White and Blue branches 

 of the river, which " automatically compensate each other, 

 so that at the time one system is passing on a large volume 

 of water, the other is storing up its discharge, and when 

 the former begins to decrease in volume the stored water 

 takes its place, and makes good the deficiency. The com- 

 prehension of these facts is, I consider, one of the most 

 "important results of our studies of the Nile since 1898." 

 Another interesting paper in the same issue of the 

 journal is that on the Panama Canal in 1908, by Dr. 

 Vaughan Cornish. The probable total cost of the work 

 is, he says, unknown, but Colonel Goethals has stated in 

 evidence that it will be at least 250, and possibly 500 

 million dollars. A lively discussion followed, in which 

 Colonel G. E. Church estimated the commerce which would 

 possibly go through the canal, if it were now complete, 

 at less than a million tons. On the question of its 

 strategic value he was equally pessimistic. The monthly 

 bibliography of geographical literature, which is a dis- 

 tinguishing feature of the journal, is as good and as in- 

 dispensable as ever. 



An interesting work of engineering is being carried out 

 in the construction of a railway tunnel under the river 

 Detroit, which runs between the United States and Canada. 

 There are no fewer than five railways that cross this river 

 between Windsor and Detroit, the service being main- 

 tained by means of ferry-boats of such a size that there 

 is room on deck for a complolc passenger train or half 

 a freight train. The time occupied in crossing the river, 

 which is half a mile wide, including the loading up of 

 the trains and the crossing, is from thirty to forty minutes 

 for a passenger train, goods trains being often delayed 

 three to four hours. The tedious delays in the transport 

 of passengers and goods occasioned by the crossing of the 

 river have for some time p'ast been the constant subject of 

 complaint, and various schemes have been brought forward 

 to remedy this. A bridge is impracticable, owing to the 

 interference it would cause to the river traffic between the 

 Great Lakes, this being equal in tonnage to that which 

 passes through the Suez Canal. Finally, a scheme was 

 settled for a tunnel, the method of construction adopted 

 being somewhat novel. This tunnel consists of two steel 

 tubes placed 42 feet below the surface of the river, each 

 i6i feet in diameter, running parallel with each other, 

 NO. 2055, VOL. So] 



but 3 feet apart. For the reception of these a trench is 

 first dredged in the bed of the river, which consists of 

 clay, 48 feet wide at the bottom ; as this proceeds piles 

 are driven in the bottom of the trench by a floating pile- 

 driver, and on these is laid a steel and concrete grillage, on 

 which the tubes are bedded. These are made of riveted 

 steel, each 262 feet long, 23 feet 4 inches inside diameter. 

 These weigh 600 tons, and are made at a yard twenty- 

 four miles distant, and conveyed to the site of the tunnel 

 by water. Before launching the ends are plugged by a 

 timber bulkhead. When the tubes are in position, inlet 

 and outlet valves are opened, causing them to sink. 

 Divers are employed to ensure that the diaphragms rest 

 firmly on the grillage. The forward end of each tube has 

 a sleeve 17 inches long, which fits over the end of the 

 tube previously sunk, the flanges being bolted to the one 

 previously laid. The trench in which the tubes are placed 

 is then filled up with cement concrete, completely embedding 

 them. The concrete is lowered through 12-inch tubes 

 from a barge. When completed, the trains are to be 

 worked through the tunnel by electricity. 



To the Museum Conference held last year in Ipswich the 

 Rev. J. S. Whitewright contributed a paper on pioneer 

 museum-work in China, which is printed in the February 

 number of the Museums Journal. The author, it appears, 

 opened in 1887 a small museum in the city of Ching-chon- 

 fu, in Shantung, with the view of opening the minds of 

 the Chinese and of establishing a basis of common 

 interests. The result was, on the whole, successful. One 

 member of the upper classes was, indeed, inclined to be 

 supercilious, and stated that there could be no such thing 

 as electricity ; if there were, the Chinese would have 

 known all about it years ago. An introduction to a 

 magneto-electrical machine convinced the sceptical visitor 

 of his error, and he left the premises a more enlightened, 

 if a sadder, man, with a full conviction of. the powers of 

 electricity. The exhibits in the museum consisted "prin- 

 cipally of maps and globes, diagrams illustrative of 

 elementary physiography, geology, astronomy, and natural 

 history, specimens of natural-history objects and manu- 

 factures, electrical apparatus, and models of engines. 



A CLASSIFIED and selected catalogue of botanical publica- 

 tions, including a number of rare books, has been received 

 from the publisher and second-hand bookseller, W. Junk, 

 of Kurfiirstendamm, Berlin. It contains a list of nearly 

 seven thousand titles ; the prices are apparently for new 

 copies where these are obtainable, but in other cases for 

 second-hand copies. The catalogue is intended to be. kept 

 for reference purposes, as it is printed on good paper, 

 bound, and furnished with a preface, in which the publisher 

 discourses chiefly on prices. 



A CONTRIBUTION by Prof. G. Haberlandt to the Sitsungs- 

 herichtc tier kaiscrlichen Akademie der Wissenschaftcu 

 (vol. cxvii., part vi.), Vienna, on sense-organs in leaves, is 

 noteworthy because it furnishes a reply to an adverse 

 critic regarding the existence of such devices in a number 

 of common plants. The author takes each species in 

 detail, and finds in every case arrangements of one kind 

 or another which he regards as functional. In Sorbite 

 Icrminalis the arrangement is provided by a cup-shaped 

 depression of the mucilage ; the shape of the cells is peculiar 

 in Chelidonium majus and Phyteuma spicatum, and in 

 Morus alba it is maintained that the cystolith, being of a 

 special type, might function as a light collector. 



A STUDY by Messrs. W. W. Robbing and G. S. Dodds 

 of the plant distribution on the slopes known as " mesas," 



