498 



NATURE 



[September 20, 1900 



size of conductors, in square inches, number and diameter of 

 strands, resistance in standard ohms per looo yards, and weight 

 in lbs. per looo yards. It is proposed to adopt the sizes and 

 combinations of conductors shown in the table as the basis for 

 tenders, beginning on October i . 



The list is now completed of the subjects to be discussed at 

 the International Botanical Congress to be held in Paris from 

 the first to the tenth of October, in connection with the Exposi- 

 tion, and promises a time of varied interest from both a struc- 

 tural and an economical point of view. Those who wish to 

 become members, and thus to obtain the results of the Congress, 

 should send their subscriptions (20 fr.) to M. H. Hua, Treasurer 

 to the Congress, 2 Rue de Villersexel, Paris. 



Five additional cases of plague, of a mild type, were reported 

 in Glasgow on Monday. This raises the total to twenty-two 

 plague cases, one suspected case, and ,115 persons under obser- 

 vation. The attacked persons had been in contact with plague 

 cases. Prof. Muir states in his report on the new cases that his 

 experiments show without doubt that the bacillus was that of 

 bubonic plague. He examined nine cases, both microscopically 

 and by means of cultures, and found the same results. 



At the Geographical Congress at Berlin in October 1899 it 

 was decided to form an International Seismological Society. 

 The first meeting of the delegates from different countries will 

 be held at Strassburg on April 11, 1901. The principal subjects 

 chosen for discussion are : The organisation and extension of 

 macroseismic investigations in all countries, the organisation of 

 international microseismic observations, the selection of 

 apparatus for international and local seismic observations, the 

 annual publication of international seismic reports, and the 

 statutes of the new society. 



The Liverpool Marine Biology Committee's station at Port 

 Erin has been very fully occupied during the greater part of 

 the summer, and there are at present half-a-dozen workers 

 doing original research in the laboratory. On Saturday last a 

 party of the Isle of Man Natural History and Antiquarian 

 Society proceeded to Port Erin on a visit to the laboratory, 

 and were heartily welcomed by Prof. Herdman, F. R.S. Mr. 

 Isaac C. Thompson gave a lecture, "On the Place of the 

 Copepoda in Nature." It was pointed out that the copepoda 

 are of the utmost value as scavengers, as they live on the 

 products of decomposition, putrefaction, drainage matter, &c., 

 and by their internal laboratories convert refuse matter into 

 most valuable food material, some copepoda constituting one 

 of the chief sources of food for fishes, and therefore of man. 

 Mr. Thompson said that no less than 200 species have been 

 found in Liverpool Bay. Their beautiful organisation illustrates 

 the truth that the wonderful structure of some animals, which 

 can only be studied with the microscope, shows them to be as 

 full of interest as those familiar to our ordinary vision. Besides 

 the many free swimming copepods, there are many species 

 found as fish parasites, living on the gills and on other external 

 parts of our common fishes ; some of these are nourished by 

 the fish and do harm, while others do not, their presence 

 being rather an advantage than otherwise. 



The importance of an organised and continuous system of 

 rainfall observations is obvious to every one possessing sufficient 

 knowledge of physical geography to know the relation of rain- 

 fall to agriculture, water supply, and all questions in which the 

 development of natural resources is concerned. It is as essential 

 that such observations should be systematically carried on in a 

 thickly populated country like our own as it is that they should 

 be made in all parts of the British Empire in which observers can 

 be found. And when stations have been established, it is again 

 essential that there should be a central bureau in which the obser- 

 vations can be collected, and their relation to one another, and to 

 NO. 161 2, VOL. 62] 



the natural features of the district determined. A report, by Mr, 

 F. R. Johnson, upon irrigation and water supply, rainfall, and 

 water rights in Cape Colony, published in the Cape Agricultural 

 fournal (August 2), issued by the Department of Agriculture, 

 reminds us of the value of continuous rainfall records in con- 

 nection with works for irrigation and water supply. It is unusual 

 for stream flow measurements, owing to their cost, to be avail- 

 able, even in the most favourable circumstances, to anything like 

 the same extent, and it is therefore very necessary that the 

 rainfall records should be carefully discussed, and full 

 advantage taken of all they are capable of teaching, so that when 

 considered and compared with shorter periods of stream flow 

 measurement (possibly only available for an adjoining catch- 

 ment) the significance of the whole may be appreciated and 

 understood. So far this has not been done in Cape Colony, 

 from an engineering point of view, and the need of the informa- 

 tion is felt now that the hydrographic conditions of the Colony 

 are being investigated. From the rainfall observations so far ex- 

 amined, it appears that sufficient water should be available to 

 irrigate about five million acres of arable land ; and when it is 

 considered that this means an enhanced land value in the Colony 

 of upwards of a hundred million pounds, the advantage of set- 

 ting to work at once to digest and apply the data available to 

 specific proposals for irrigation is apparent. 



In an article on " The Amount of the Circulation of the Car- 

 bonate of Lime and the Age of the Earth," by Prof. Eug. 

 Dubois {K. Akad. van Wetenschappen te Amsterdam, 1900), it 

 is conceded that the ocean, which derives all of its carbonate of 

 lime from rivers or the waste of sea-cliffs, holds as much of it 

 as it can, and that rivers are incessantly bringing a surplus. 

 A considerable amount of carbonate of lime is often to be found 

 in the matter carried in suspension by large rivers to the ocean, 

 and it is obvious thac in these river-waters the solution must be 

 saturated. The quantity of carbonate of lime in river- waters is 

 naturally determined by the rocks in the drainage areas. The 

 author gives reasons which lead him to conclude that not more 

 than one-thirtieth part of the carbonate of lime which rivers now 

 discharge into the ocean' is newly formed from silicates, although 

 originally all was so derived. His calculations, based on the 

 amount of carbonate of lime annually carried to sea by rivers, 

 show that the formation of the whole estimated minimum, 

 amount of carbonate of lime on the earth would require about 

 45,000,000 of years, and that of the real amount a much larger 

 lapse of time. He estimates that 1/2, 7 70,000th of the total 

 quantity of carbonate of lime of the earth participates annually 

 in the present circulation. The final result of his investigation,, 

 though admittedly only suggestive, is that the real lapse of time 

 since the formation of a solid crust and the appearance of life 

 upon the globe may be more than a thousand million of years. 



Mr. a. Gibb Maitland, Government geologist of Western. 

 Australia, has issued, as Bulletin No. 4 of the survey reports, a. 

 general account of " The Mineral Wealth of Western Australia. "^ 

 This work is intended to replace the useful mining handbook 

 which was prepared by Mr. Harry P. Woodward, and has long, 

 been out of print. The author gives a sketch of the geological 

 features of the Colony, and then deals specially with gold,, 

 lead and copper, tin, iron, miscellaneous minerals (such as 

 antimony, zinc, &c.), coal and graphite, guano and artesian 

 water (with records of borings). A full list of minerals is 

 appended, and there is a map showing the distribution of 

 useful minerals in Western Australia, and five geological maps 

 of particular mineral districts. The guano, which is obtained 

 from the Abrolhos Islands and elsewhere in the north, is an< 

 important product. In 1899 upwards of two thousand tons 

 were obtained, the total value being over 5000/. The amount 

 raised last year was, however, small compared with some 

 previous records. 



