Aur.uST 27, 1896] 



A' A TURE 



403 



3-36 mc-tres, and the velocity of the paper to about 15 mm. per 

 minute. The diagrams are of course distorted in theidirection 

 in whicli the paper moves, and they no longer give the exact 

 times ul particular phases ; but, aclinj; in concert with the older 

 form, the new microseismograph furnishes valuable data with 

 regard to the character and direction of the pulsations. In the 

 paper by Prof. Vicentini and Dr. Pacher, in which these changes 

 are described (Atlidel A'. 1st. Vcucto.ii scietnc, &c., vii., 1S96), 

 two interesting diagrams are reproduced, both corresponding to 

 very distant, but unknown, earthquakes— one on December 25, 

 1895, ""'' the other on January 15, 1S96. 



Wk have received from Dr. Joachim Sperber, of Zurich, a 

 hroihiirc of 37 pp. on the parallelogram of forces regarded 

 as the basis of the periodic system in chemistry. After 

 applying the principle to a number of numerical calculations, the 

 author remarks in conclusion, that the stereochemistry of carbon 

 and nitrogen is nothing but a case of resolution into components 

 in different directions. The paper is published by E. Speidel, 

 of Zurich. 



Among the 300 species, or thereabouts, of plants which 

 Lundstriim and others describe with more or less accuracy as 

 acarophilous, no gymnosperms or monocotyledons have hitherto 

 been included, but Dr. de (lasparis, in the Kciidiionlo dclla R. 

 Acuid. dellc Scienze fisiche e matemalidic (Naples), describes a 

 monocotyledon Scindapsits dilaceratus as having Acarus-%fiX\% 

 produced freely at the bases of the leaf-segments. He describes 

 them as being produced undoubtedly as the result of puncture, 

 and details the changes which take place in the mesophyll of the 

 leaf, resulting in a small chamber surrounded by many layers 

 of special cells. Although he apparently accepts Lundstrom's 

 view that these Acarus-^3!i\% are a strict case of symbiosis, the 

 plant profiting alike by the secretions of the Acari, and by the 

 latter consuming fungus spores, &c., which otherwise might 

 germinate upon the epidermis of the plant, he produces no 

 evidence to show that in this particular case symbiosis exists 



We have received from the agricultural department of the 

 Glasgow and West of Scotland Technical College a brochure of 

 seventy pages, embracing reports on experiments on the manuring 

 of oats, hay, and turnips, on finger-and-toe in turnips, and on 

 the spraying of potatoes, conducted in 1895 ^y Prof. R. P. 

 Wright and others on farms in the south-west and centre of 

 -Scotland. The results of the experiments upon the oat-crop 

 indicate that nitrogenous manures, such as nitrate of soda and 

 sulphate of ammonia, applied alone, retard ripening, but give 

 large and profitable, though somewhat irregular, increases of 

 crop ; also that these nitrogenous fertilisers are more uniform 

 and more regular in their action when applied with a soluble 

 phosphatic manure, particularly superphosphate of lime. In the 

 case of the fungoid disease finger-and-toe — known also as club- 

 root or anbury — confirmation is afforded of the previously 

 ascertained fact that liming, if done early, will benefit a crop of 

 turnips on land where the disease is prevalent. The spreading 

 out on lea land of diseased roots to be consumed by stock is very 

 properly condemned. It may be mentioned that finger-and-toe 

 is very prevalent this season, especially in Scotland and the 

 North of England, and it is no doubt a source of serious loss ; 

 the pathogenic organism is Plastiwdiophora brassica. It is 

 difficult to understand why the spraying of the potato crop with 

 bouillie bordelaise. as a check upon the potato disease, should 

 give such indifferent results in Scotland, whilst the practice has 

 been attended by substantial benefit in England and France, and 

 particularly in Ireland. We quite agree that, at present, " it 

 would be rash to draw definite conclusions" from the general 

 results of the experiments that have hitherto been made in 

 Scotland. 



NO. 1400, VOL. 54] 



Messrs. G. Bei.l \sh Sons have sent us an advance pro- 

 spectus of a work they are about to publish under the title 

 " :Men and Women of the Century." The work comprises a 

 series of portraits of notable men and women who have sat to 

 Mr. Rudolf Lehmann between the years 1847 and 1895, each 

 portrait signed with the autograph of the sitter. There will be 

 twelve photogravures, from paintings, and about seventy fac- 

 simile reproductions of the drawings in half-tone, some of them 

 printed in colours, and all executed by the Swan Electric 

 Engraving Company. Among the scientific men whose bio- 

 graphies and portraits are given are the following : — A. von 

 Humboldt, Louis Pasteur, Sir Richard Owen, Prof. Virchow, 

 Prof. Huxley, Prof. Burdon Sanderson, Prof. Mommsen, Prof. 

 Max Miiller, Prof. Du Bois Reymond, Sir William Siemens, 

 von Ranke, Sir David Brewster, Sir Henry Bessemer, and Sir 

 Spencer Wells. The collection will thus form an intei-esting 

 private gallery of contemporary portraits. It is edited by Mr. 

 H. C. Marillier, who contributes an introduction and the short 

 biographical notices. 



The additions to the Zoological Society's Gardens during the 

 past week include a Capybara {Hydrocluirus capybara) from 



South America, presented by Mr. F. W. Temperley ; a 



Fox \Canis ■ — -) from Nicaragua, presented by Mr. F. A. 

 Pellas ; a Black-necked Grackle [Graciipica nigricollis) from 

 China, presented by Dr. Nowell ; a Salt-water Terrapin {Clem- 

 mys terrapin) from Florida, presented by Miss Hole ; two Brush 

 Turkeys ( Talegalla lathaint) from Australia, deposited ; a Yak 

 (Poi'phagus griinitieiis, (J ) ; an English Wild Cow (j5(7^ tauriis 

 var. ), a Wapiti Deer (Cci-viis laiiadensis^ 9), born in the 

 Gardens. 



OLTR ASTRONOMICAL COLUMN. 

 Astronomical Constants. — Some account of the com- 

 pleted work of Drs. Gill and Elkin on the determination of 

 astronomical constants by means of heliometrical measurement 

 is given in the Bulletin Astronomiijue for August. The values 

 there given differ by minute amounts from those contained in the 

 preliminary paper published in the Monthly Notices for April 

 1894. For Solar Parallax the following values have been 

 derived : — 



The value given by the Iris measures is slightly greater than that 

 from the other asteroids, and the suggestion is made, but not 

 insisted upon, that this might be explained by the light of Iris 

 being somewhat less refrangible than that of the stars with which 

 it has been compared, a fact that Dr. Elkin has noted in the 

 course of his observations. Prof. Newcomb has pointed out 

 that a not impossible difference between the spectrum of the 

 planet and star could affect the resulting parallax to the extent 

 of two or three hundredths of a second. Since, however, the 

 mean value of the parallax does not differ from that derived from 

 the observations of Iris by more than the probable error, no 

 definite conclusion can be drawn on this point. 



The value of the moon's mass, derived from the discussion of 

 the observations of Victoria is 



= 0-012240+0-000015. 



81-702 ± 0-094 



This result is believed to be free from the effects of any systematic 

 errors. 



The Constant of Nut.ation is given as 9-206S"+o-oo34'', a value 

 that lies midway between the generally accepted values of New- 

 comb and Chandler, viz. 9-210" and 9-202" respectively. This 

 satisfactory agreement again points to the successful elimination 

 of all systematic errors. 



Small Planet Observations.— The asteroid Abundantia, 

 No. 151, has offered for solution a very curious problem. Since 

 its discovery in 1875, it has been observed, or at least 



