December 14, 1893] 



NA TURF. 



161 



however, obtained when broth was purposely added to the un- 

 filtered water, an addition of as liltle as 5 c.c. to 6oo c.c. of 

 water so stimulating the growth of the typhoid organisms, that 

 two days later they appeared in the filtrate ; the numbers 

 present, however, gradually decreased, but on again adding 

 5 c.c. of broth they rose on the following day from 9 to 6,139 

 per c.c. This large increase was due to the rapid multiplication 

 of the few isolated bacilli still remaining in the pores of the filter 

 in consequence of the supply of food material to the water in 

 the shape of broth, for no fresh infection with typhoid organisms 

 had taken place. Dr. Schiifer is of opinion that typhoid bacilli 

 as present in water, under ordinary circumstances, are not sup- 

 plied with the requisite conditions for their growth and multi- 

 plication, and are, therefore, incapable of growing through these 

 porous filters, and so reaching the filtrate ; but these conditions 

 are, however, undoubtedly furnished when a sufficient supply of 

 food material is contained in or added to the water, under which 

 circumstances the cylinders are unable to retain them. These 

 experiments not only explain the unsatisfactory results obtained 

 by Kirchner, but indicate what precaution? should be taken in 

 the bacteriological investigation of such filters. 



The last two parts of the well-known "Notes from the 

 Leyden Museum," forming parts 3 and 4 of vol. xv., were pub- 

 lished in July and October. They contain numerous papers 

 describing new or rare species of mammals, birds, reptiles, &c. , 

 added to the museum. Among the articles we notice one which 

 is by F. E. Blaaum, the Secretary of the Z )ological Society of 

 Amsterdam, on a comparative list of the birds of Holland and 

 England. Holland, although so much smaller than the United 

 Kingdom, is the regular abode, at different seasons, of 221 

 species of birds, whilst the British Islands can only boast of 

 211. Dr. R. Horst continues his descriptions of earth-worms, 

 giving a list of species found, for the most part by Dr. 11. ten 

 Kate, during his journey in the Malay Archipelago in 1891. A 

 large number of the species belong to the geu'is Perichasta, of 

 which no less than seven species are described as new, bringing 

 the number of the species of this genus already found in the 

 Malay Archipelago to thirty-three. The following note, by Dr. 

 Jentink, will be interesting to others besides book collectors. In 

 the Proceedings of the Ziological Society of Lond)n for i8So 

 (p. 489), Mr. F. II. Waterhouse gives the dates of the publica- 

 tion of the parts of Sir Andrew Smith's "Illustrations of the 

 Zoology of South Africa," and states that as the copy he examined 

 "did not contain plates 18 and 38 (Mammalia), he had examined 

 three or four other copies, and as neither of these pUtes are 

 to be found in any of these, he presumed they do not exist." 

 Now, in the copy in the Leydea Museum's library, plate 3S is 

 present, but plates iS and 37 are wanting, and at the bottom of 

 the page containing an index of the Mammalia, there is the 

 following : " Plates 18 and 37 7iot published." Librarians will 

 call to mind how often the collating of this fine work has 

 perplexed them. 



The Royal Meteorological Institute of the Netherlands has 

 recently issued its Jaarboek and Onweders in Nederland for the 

 year 1892. The first work has been regularly published for 

 forty-four years, and now contains hourly observations taken at 

 four stations, in addition to those taken at specified hours at a 

 number of other places. It also contains observations taken in 

 Surinam (South America) and French and Upper Congo. The 

 second work is the thirteenth of the series, and contains a dis- 

 cussion of each of the ihunderstorms which have occurred dur- 

 ing the year, with reference to the general weather conditions 

 over Europe. 



We have received from Mr. John Elliot, the Meteorological 

 Reporter to the Government of India, the daily weather charts 

 of January, 1893, for the Indian sea and land areas. 

 NO. 1259, VOL. 49] 



MM. J. B. Baillu'cre et Fils, Paris, have issued an 

 ornithological bibliography containing announcements of five 

 or six hundred works on ancient and modern bird-. 



Herr Moritz, Berlin, has published Nos. 1-4 of his " Anli- 

 quariats-Katalog." The catalogues are of special interest to 

 geographers and anthropologists, and they contain many rare 

 works. 



Messrs. Friedlander and Son, Berlin, have sent us Nos. 

 16-21 of their " Naturte Novitates." These bibliographical 

 lists contain works in every branch of science, an 1 are invalu- 

 able to the scientific book-hunter. 



Another catalogue, recently issued, is one containing the 

 titles of works on geology offered for sale by Messrs. Dulau 

 and Co. 



The first number of the Psychological Revieiv will be pub- 

 lished early in January, by Messrs. Macmillan and Co., London 

 and New York. It will be edited by Profs. J. Mark Baldwin 

 (Princeton) and J. McKeen Cattell (Columbia). The Revinv is 

 intended to contribute to the advancement of psychology by 

 publishing the results of original research, constructive and 

 critical articles, &c., in connection with the subject. 



The American Naturalist for November contains several in- 

 teresting articles. Mr. Howard Ayers writes on the genera of 

 the Dipnoi Dipneumones, and Dr. J. Weir gives a number of 

 examples of animal intelligence. A collection of molluscs from 

 North-Western Louisiana is described by Mr. T. Wayland 

 Vaughan, and Mr. H. C. Mercer compares the Trenton and 

 Somme gravel specimens with ancient quarry refuse in America 

 and Europe. 



Messrs. Newtox and Co. have issued a new catalogue of 

 optical lanterns, microscopes, and polariscopes fir demonstra- 

 tions in science. There are very few class experiments that do 

 not admit of being projected upon a screen by means of the 

 many good lanterns in the market, and certainly there is no 

 better method of demonstrating scientific facts to a large audi- 

 ence. One of the finest lanterns made by Messrs. Newton is 

 the tiiple rotating electric lantern designed by Sir David 

 Salomons. We learn that the Royal Society has just ordered 

 an instrument of this kind. 



A general method of artificially preparing crystallised 

 anhydrous silicates similar to the naturally occurring pyroxenes, 

 is described by Dr. Hermann Traube in the current Berichte. 

 It consists in precipitating the particular metallic silicate, which 

 it is desired to obtain in anhydrous crystals, by the addition of 

 a solution of sodium silicate to a solution of a s-alt of the metal. 

 The amorphous hydrated silicate thus precipitated is heated to 

 a high temperature with boric acid for some hours. When most 

 of the boric acid has volatilised, the anhydrous metallic silicate 

 is usually left in the form of good crystals. Ebelmen has 

 already succeeded in artificially preparing the magnesium 

 pyroxene MgSiOg by this method ; and Dr. Traube now ex- 

 tends its application. When precipitated silicate of zinc, for 

 instance, obtained by the addition of a solution of sodium sili- 

 cate to one of zinc sulphate, is dried, and then heated with 

 eight times its weight of fused boric acid, in a platinum crucible, 

 for a few days, to the highest temperature of a porcelain manu- 

 facturer's furnace, a large proportion of the boric acid dis- 

 appears by volatilisation, and upon extraction of the remaining 

 portion from the cooled residue with water, beautiful little in- 

 soluble crystals of anhydrous silicate of zinc, ZnSiOj, remain. 

 When examined under the microscope these crystals are observed 

 to be perfectly transparent prisms with domal terminations. 

 Their optical characters indicate that they belong to the rhombic 

 sjstem of symmetry. This artificial silicate of zinc would thus 



