12 



NA TURE 



{Nov. 29, 1 1 



benches are ranged down each side of the length of the room, and 

 are all fitted with gas and water ; and ample storage room is pro- 

 vided by four capital cupboard-cases. An excellent lecture-table 

 occupies the usual position ; the sand-bath and still are of copper, 

 and heated by Fletcher's burners. There is also a convenient 

 master's room, which, when finished, will be very complete. 



Prof. H. G. Seeley, F. R.S., is about to deliver a course of 

 lectures on the practical study of the geology of the country 

 round London. This course is given at the request of students 

 of the London Geological Field Class ; and infor jaation concern- 

 ing the lectures may be obtained from Mr. William Dunn, 21 

 King William Street, Strand, W.C. 



The Penny Science Lectures at the Royal Victoria Hall for 

 the month of December will be as follows : — December 4, on 

 ■"Nature's Hot Springs," by Dr. S. Rideal ; December 11, on 

 ^'Limestone Rocks and their History," by Mr. E. Wethered. 

 The series will begin again on January 22, 1889. 



At a conversazione, given by the Oxford University Junior 

 Scientific Club, on Friday, November 23, in the University 

 Museum, Prof. Milnes Marshall, of the Owens College, 

 ■delivered a lecture on " Animal Pedigrees," which was highly 

 ajjpreciated by a numerous company of members of the Univer- 

 sity and their friends. Later in the evening Colonel Gouraud 

 introduced and explained the new Edison phonograph. The 

 members of the Club further entertained their guests by varied 

 scientific exhibits and demonstrations, while the band of the 60th 

 Royal Rifles enlivened the proceedings with music. 



The Duchess of Albany has consented to become Patroness 

 of the Sanitary Institute. 



A GIGANTIC stalactite cave has been discovered near Riibe- 

 land, in the Harz Mountains, surpassing the neighbouring 

 Bauman's Cave in size and beauty. Some excellent photographs 

 of different parts of the cave were taken by Dr. Max Miiller, of 

 the Brunswick Technical High School, by means of the electric 

 light. These photographs are shortly to be published, accom- 

 panied by explanatory notes by Prof. Kloss, of Brunswick. The 

 cave is to be lighted by electricity, and opened to the general 

 public next year, after precautions have been taken to keep it 

 in its present perfect state. 



During the last summer Dr. Otto Zacharias examined care- 

 fully the crater " Maare " (lakes) of the volcanic Eifel. They 

 are inhabited by numerous species of Copepoda, Daphnidse, 

 Radiolaria, Rotifers, water mites, and insect larvae. The largest 

 of the " Maare," the Laacher See, which measures about seven 

 miles in circumference, contains a special fauna. Besides this 

 lake, Dr; Zacharias examined four others : the Pulvermaar, 

 Holzmaar, Gemiindener Maar, and Schalkenmehren Maar. 



At the meeting of the Royal Meteorological Society on 

 November 21, Dr. A. Riggenbach, of Basle, read an interesting 

 paper on a method of photographing cirrus clouds. Great 

 difficulty is experienced in obtaining photographs of cirrus clouds, 

 the reason being that the blue light of the sky acts with nearly 

 the same actinic energy as the white light of the clouds on the 

 sensitive silver salts of the plate. What is wanted is that this 

 blue light of the sky should be dulled, the light of the clouds 

 being left unaffected, and this can be done by means of the 

 analyzer of a polarizing apparatus. The light from the blue sky 

 is partly polarized, and to the largest extent at the points which 

 are situated 90° from the sun ; the plane of polarization passing 

 through the points looked at, the sun, and the eye of the observer. 

 On the other hand, the light coming fro:n a cloud is only polar- 

 ized to a slight extent. Having spoken of what can be done by 

 the use of a Nicol's prism, Dr. Riggenbach went on to say that 

 we might substitute for a Nicol's prism a dark mirror, a painter's 



mirror, or, best of all, a plate of obsidian. If such a plate be 

 held so that the plane which passes through the cloud, its 

 reflected image, and the eye, is normal to the line from the 

 observer to the sun, the mirror extinguishes the polarized light 

 from the sky almost completely, and the reflected image of the 

 cloud comes out sharp on a dark background. If such an 

 obsidian plate be fixed before the lens of a photographic camera, 

 so that its plane is inclined at an angle of 33° to the optical axis 

 of the lens, and the camera be placed so that the sun's rays 

 shine perpendicularly on one of its sides, we then turn the whole 

 apparatus round, in the direction in which the sun lies, as an 

 axis, until a cirrus cloud is visible in the camera. If a sensitized 

 plate be inserted, a picture of the cloud can be produced under 

 the most favourable conditions possible. A still simpler mode 

 of obtaining such cloud pictures is to use the surface of a lake 

 as a polarizing mirror. The best clouds for such a purpose are 

 those at sunrise or sunset, at an altitude of about 37°, and in 

 an azimuth either greater or less than that of the sun by 90°. 



The North Atlantic Pilot Chart for November states that 

 the most noteworthy disturbance during October was a West 

 Indian hurricane which developed near Yucatan on the 9th, and 

 reached the south coast of Long Island on the I2th. The 

 tracks of all the depressions moving eastward from the American 

 coast during the first half of the month lay well to the northward 

 of the normal path until reaching the 55th parallel. This is 

 very interesting in connection with the persistence with which 

 an energetic area of high barometer lingered over the middle of 

 the Atlantic, and afford-; a good illustration of the tendency of 

 areas of low pressure to avoid those of high. Only one iceberg, 

 near Belle Isle, was reported. 



• W^E have received the Report of the Meteorological Service 

 of the Dominion of Canada for the year 1885, which shows con- 

 tinual progress and improvement in the various departments. 

 In addition to the Annual Reports, containing the results for 

 numerous stations, a Monthly Review is published giving a 

 general restimc of the weather throughout the Dominion, and an 

 analysis of the daily forecasts and storm warnings. The weather 

 signals carried on the railway cars are much appreciated, both 

 by the farming community and the general public. New stations 

 are established in the more remote districts as opportunities 

 offer, and many valuable observations are also obtained along 

 the line of the Canadian Pacific Railway, in regions where it is 

 difficult to get observers other than the station officials. 



Two fine series of salts of two new platinum bases CDntaining 

 sulphur and organic radicles have been prepared by the Swedish 

 Professor Blomstrand and his assistants, of Lund. They will 

 form a striking addition to the now large number of these re- 

 markable platinum compounds, which have been obtained since 

 the preparation of the first of their class, the well-known green 

 salt of Magnus, in 1828. When a solution of potassium platinous 

 chloride, KaPtC^, is shaken with two molecular equivalents of 

 ethyl sulphide (C2Hg)2S, a quantitative precipitation of a yellow 

 chloride, of the composition ■ptS(C2H5)2 . S(C2H5)2C1^ occuis. 



On treating this somewhat complex substance suspended in water 

 with another two equivalents of ethyl sulphide, the whole eventu- 

 ally dissolves, with the exception of a small quantity of an oily 

 substance, which appears to be formed as a secondary product. 

 On allowing the separated clear liquid to stand, it gradually 

 deposits crystal crusts of greenish-yellow monoclinic tables 



of the chloride of the first new base, Pt^Sc^H^j-ci- I" ^ 

 similar manner. Prof, Blomstrand has obtained the bromide, 

 Pt[S(C2H5)2Br]2, which crystallizes in reddish-yellow monoclinic 

 prisms ; and the iodide, which resembles the bromide very closely, 

 but forms beautiful dark-red monoclinic crystals of considerable 

 size. In addition to these well-defined halogen salts, the nitrite 



