March 13, 1879] 



NATURE 



447 



in Europe, received at these stations, will be graphically re- 

 jiresented on maps, and these maps w ill be exhibited between 

 four and five P.M. at a central point of the town, under glass, 

 fur public use. Besides there will be given a prognostic of 

 V eather for the following day ; and this information will be sent 

 to each commune and person w ho will pay monthly the sum of 

 15 francs. This system is already introduced in Zurich and 

 Eeme, and the prognostics are correct in eight cases out of ten. 



We have received from Mr. Downing, of Whiskin Street, a 

 neat little cabinet of twenty specimens of rocks, fossib, and 

 minerals to illustrate Geikie's Geology Primer. Considering the 

 number and quality of the specimens, and their suitability for 

 the purpose, the cabinet is a wonder of cheapness, and ought to 

 have a wide sale. 



In view of the apparently insurmountable difficulties which 

 attend the completion of the New National Opera House on the 

 Victoria Embankment, the Globe understands that all the agents- 

 general for the different colonies have entered into negotiations 

 for the purpose of securing this site for the proposed Colonial 

 Museum. 



Interesting correspondence has appeared in the British 

 Guiana' ^(Ty^/ Gazette, we learn from the Colonies and India, rela- 

 tive to the qualities assigned to the fruit of the papau-tree. It 

 has been recently asserted, in an article in the Pharmaceutical 

 yournal, " that the most interesting property attributed to it is 

 the power of its juice to render bad flesh tender." Mr. Monro, 

 of Georgetown, furnishes certain facts which he says are com- 

 monly known to the natives of British Guiana relative to this 

 fruit A horse tied near one of these trees rapidly loses health, 

 and a stud horse becomes useless. Any pressure on the body of 

 the animal leaves an inelastic indentation. The sap of the tree will 

 soften steel, and before the process of tempering was known in 

 the Colony, the blacksmiths used to drive their brittle chisels and 

 ]>lane vices into the wood, leaving them there for a day c r two ; 

 and tough meat wrapped in the leaf for only a few minutes 

 becomes tender, and the same thing happens if it be suspended 

 against the tree itself. The seed of the ripe fruit is an excellent 

 vermifuge, and children have a great partiality for it 



In a recent paper in the journal de Physique complementary 

 of the theory of dew, M. Jamin points out that moist surfaces 

 are subject to two superposed causes of cooling, one radiation 

 (like dry substances), the other evaporation. The difference 

 between the two actions is that the former persists at every tern- 

 perature, while the latter, at first considerable, decreases and 

 becomes nil when saturation is reached (it does not produce dew, 

 but contributes to prepare and accelerate it, for it renders the 

 air both moister and colder). The quantity of heat borrowed 

 from the air by evaporation is very considerable : I gramme of 

 eraporated water lowers about one degree the temperature of 

 2.553 grammes of air (or nearly two square metres' volume). 

 Thus is explained how moist bodies, like plants, especially 

 herbaceous, are cooled much more quickly than dry bodies. 

 The dew forms on them more quickly ; once it has commenced 

 it continues by the sole effect of radiation. In driving rapidly 

 down from a plateau into a valley one is often struck with the 

 sudden cold. This cold is probably the effect of more rapid 

 evaporation from the herbs, aquatic plants, and all moist surfaces 

 of the valley. Other facts illustrate the double effect of radia- 

 tion and evaporation, e.g., the danger of plants in early spring 

 after being moistened by a shower, and the well-known mode of 

 nunufacture of ice in Bengal. The role of dew is that of 

 moderating and sometimes arresting the nocturnal cooling, and 

 preserving plants from the early frost. 



An interesting lecture on certain enigmatical phenomena of 

 astronomy has been recently delivered by M. Houzeau before 



the Belgian Academy of Sciences, of which he is president. 

 The points he takes up are, the apparent enlargement of heavenly 

 bodies near the horizon (not adequately explained by a weakening 

 of the rays, or interposition of terrestrial objects) ; the supposed 

 satellite of Venus, observed seven times in 119 years, by eminent 

 astronomers, but quite imobserved during the 1 14 years since ; 

 the phenomena connected with Biela's comet ; the effects of the 

 earth encountering a comet (may such a thing occur? has it 

 occurred ?) ; and the zodiacal light The lecture appears in the 

 Academy's Bulletin (No. 12 of 1 878). 



We have on our table the following books : — " Text-Book 

 of the Steam Engine," T. M. Goodeve (Crosby, Lockwood, and 

 Co.) ; "The Aborigines of Victoria," 2 vols., R. Brough Smith 

 (Triibner) ; " Report of the British Association for the Advance- 

 ment of Science, 1878," Dublin (Murray) ; " The Circle and 

 Straight Line," John Harris (Werthei-ner, Lea, and Co.) ; 

 "Moore's Columbarium," reprinted by W. B. Tegetmeier 

 {Field Office) ; " Practical Treatise on the Manufacture of 

 Sulphuric Acid," A. G. and C. G. Lock (Sampson Low and 

 Co.) ; " Atlas of Histology," Part i., E. Klein and E. N. 

 Smith (Smith, Elder, and Co.) ; " Geologische Uebersichtskarte 

 des T rolisch-Venetianischen Hochlandes zwischen Etsch und 

 Piave," 6 Maps, Dr. Edmund Mojsisovics, (Vienna : A. 

 Holden) ; "Die 'Dolomit-Riffe, von Sudtirol und Venetien," 

 Heft i. to vi., E. V. Mojsisovics (Vienna : Alf. Holden) ; 

 "Meteorological Obser\'ations made at the Adelaide Observa- 

 tory, years 1876 and 1877," Ch. Todd; "Journey through 

 Khorassan," 2 vols. Col. C. M. M'Gregor (Allen and Co.); 

 " Lakes and Mountains of Africa," J. F. Elton (Murray) ; 

 "On the Annelida Chretopoda of the Virginian Coast," H. E. 

 Webster; " Fecondation des Fleurs," E. and G. Gevaert (G. 

 Mayolez). 



The additions to the Zoological Society's Gardens during the 

 past week include three Japanese Deer {Cervus sika) firom Japan, 

 presented by the Viscount Powerscourt, F.Z.S. ; a Syrian Bear 

 (Ursus sj'riacus) from West Asia, presented by Dr. J, Huntley; 

 a Green Monkey {Cercopithecus callitrichus) from West Africa, 

 presented by Miss E. A. B. Pay ton ; a Pig-tailed Monkey 

 {Macacus nemestrinus) from Java, presented by Mrs. J. E. 

 Fenton ; a Coati (N'asua iiasica), an Acouchy (Dasyprocla 

 acotichy) from British Guiana, two Mountain Finches (Ftingilla 

 montifringilla), British Isles, purchased. 



SCIENCE IN RUSSIA 



AXTE take from the just issued Annual Report of the St. 

 Petersburg Academy of Sciences for 1878, the following 

 information as to the work done by the Academy during the 

 year in the mathematical and physical sciences. 



Prof. Chebysheff has continued his researches into the proper- 

 ties of parallelograms which consist of three elements, and are 

 symmetrical with respect to one axis, these researches already 

 having led him to important results ; among them we notice his 

 general formula for determining what are the simplest combined 

 systems which, when set in motion, give a straight line. 



Prof. Minding has published two papers, one of which is an 

 important addition to his former researches on curves. 



The Pulkova Observatory has published the ninth volume of 

 its Memoirs, which contains the micrometrical measvu"ements of 

 double stars by Prof. O. Struve, during forty consecutive years. 

 The value of these very numerous and precise measiu-ements is 

 much increased by the circumstance that they were made during 

 so long a period by the same person, with the same instruments, 

 and on the same methods ; the comparison of M. Struve's obser\-a- 

 tions with those of several known astronomers affords a means 

 of reducing all of them to one system. 



The transit of Mercury was observed at Pulkova with fourteen 

 telescopes. It is worthy of notice that the observations proved 

 that Mercury does not have such a dense atmosphere as that 

 discovered around Venus. 



The interesting researches of the late Prof. Asten into the 



