April 14, 1898J 



NA TURE 



567 



The sources of commercial india-rubber form the subject of 

 two Cantor Lectures to be delivered at the Society of Arts on 

 Monday, April i8 and 25, by Dr. D. Morris, C.M.G. 



Ax instructive article upon processes of alkali manufacture, 

 with special reference to the works of Messrs. Brunner, Mond, 

 and Co., appeared in yesterday's Times. 



We have received from Mr. C. Leeson Prince the summary 

 for the year 1897 of meteorological records which he keeps 

 at his observatory on Crowborough Hill, Sussex. Perhaps 

 the most important event of the year occurred on May 30, 

 when, as he says, " a more memorable thunderstorm passed 

 over a portion of this country than has happened within living 

 memory." This storm, from all accounts, did not actually 

 occur at Crowborough Hill ; but from its elevated position the 

 progress of the storm, though twenty miles distant, could be 



may mention that the experiments appear to have been carried 

 out with great care. The thermometers were placed at various 

 depths below and heights above the ground, and show clearly 

 the effect of the soil upon the air temperature and humidity 

 during the various hours of the day and night. The conditions 

 of humidity were found to be very different between the level 

 of the ground and the height of about 33 feet (at which the highest 

 thermometers were placed), being less in the night and greater 

 in the day in the lower than in the upper strata of air. 



The Rev. W. Sidgreaves, in his report of the Stonyhurst 

 College Observatory for 1897, gives us the results of the 

 meteorological and magnetical observations made during the past 

 year, with notes and comments. In addition to these observ- 

 ations, which have been carried out with the utmost regularity, 

 other branches of work have been followed. Thus prepara- 



\,Jrroiii a Photograph by Wynter, Seaford. 

 A reproduction (natural size) of some hailstones which fell at Seaford during the thunder-storm of May 30, 1897. 



watched for a considerable time. Mr. Prince gives a repro- 

 duction of some of the hailstones which had previously fallen at 

 Seaford during the same storm These were found to be still 

 larger, as will be seen by the accompanying illustration showing 

 the hailstones in their natural size. 



We have received from Dr. T. Homen, of the University of 

 Helsingfors, a laborious investigation, entitled " Der tagliche 

 Warmeumsatz im Boden und die Warmestrahlung zwischen 

 Himmel und Erde," being a continuation of a work published 

 in 1894, in which the author dealt more particularly with earth 

 temperature, evaporation and dew. In the present publication 

 Dr. Homen attempts the determination of the amount of heat 

 which enters various kinds of soil during the day, and the 

 amount given up by radiation during the night. We are un- 

 able to give an adequate account here of the various interesting 

 results contained in a quarto volume of about 150 pages, but we 



NO. 1485, VOL. 57] 



tion was made for photographing trails of the November 

 meteors, five cameras having been mounted round the object- 

 glass end of the equatorial, but the weather proved too un- 

 favourable. Again, 174 drawings of solar spots and faculoe 

 were made during the twelve months, and enlarged drawings of 

 spots near the solar limb were undertaken to obtain evidence 

 about the level of the umbra. As regards stellar spectroscopy 

 240 plates were exposed, the work in hand being directed to the 

 sequence of spectrum differences of the yellow and red stars, from 

 those of the solar type to the type of o Herculis. An appendix 

 to this report contains the results of meteorological observations 

 for 1897, made at St. Ignatius' College, Malta, by the Rev. J. 

 F. Dobson. 



Science states that in addition to the plans of the Geological 

 Survey for explorations in Alaska, the Treasury Department are 

 about starting five or six expeditions to explore the Yukon river, 



