June, 1913. 



KNOWLEDGE. 



221 



force eleven, five force ten, and nine force nine, out of a total 

 of forty-seven. By noon of the 11th the storm was central 

 near 56° N. and 15° W., and winds of force seven to eleven 

 were prevailing over the ocean north of the fortieth parallel 

 and east of the forty-fifth meridian. Severe gales occurred 

 over the British Isles. 



LOWEST BAROMETER RECORDS 

 with the above remarkably low 

 reading of 26-96 inches it may 

 be of interest to give what is, 

 so far as is known, the next 

 actual lowest barometric pres- 

 sure which has been observed in 

 any other part of the world, viz., 

 27-135 inches on September 

 22nd, 1885, at False Point, on 

 the coast of Orissa, India. In 

 the British Isles the lowest 

 recorded barometric pressures 

 have been: — 27-332 inches on 

 January 26th, 1884, at Ochter- 

 tyre, Crieff; and 27-380 inches 

 on December 8th, 1886, at 

 Belfast. 



-In connection 



VIOLENT UPRUSHES IN 

 CUMULUS CLOUDS.— Every- 

 one who has carefully watched 

 clouds is familiar with the 

 peculiar boiling and tumbling 

 of large cumulus clouds, their 

 formation of new heads, and 

 the other evidences they often 

 give of violent motions and an 

 explosive-like turbulence. The 

 late Dr. W. von Bezold suggested 

 that these movements indicate 

 that there is a source of power 

 within the cloud itself, and he 

 ascribed this power to the latent 

 heat set free by the more or less 

 sudden condensation of a super- 

 saturated vapour, or the sudden 

 freezing of undercooled water- 

 drops. 



Professor W. J. Humphreys has recently investigated this 

 subject, and he has come to the conclusion that the difference 

 in temperature between the free air and the interior of large 

 cumulus clouds at the same level is the 

 real cause of the violent uprush and turmoil 

 in their centres. He is also of opinion 

 that most of the electrical and other energy 

 of the thunderstorm comes directly or 

 indirectly from the latent heat of conden- 

 sation set free within the mass of turbulent 

 cumulus clouds. 



PHENOLOGICAL OBSERVATIONS, 

 1912. — At the meeting of the Royal Meteor- 

 ological Society on April 16th Mr. J. E. 

 Clark and Mr. R. H. Hooker presented 

 their report on the Phenological Obser- 

 vations for the year ending November, 

 1912. This dealt with the dates of the 

 first flowering of certain plants, the song 

 and migration of birds, the appearance of 

 insects, and the yield of farm and fruit 

 crops. The chief factors affecting the field 

 crops were probably the dry warm April 

 and May, followed by the cold, wet, sunless 

 summer. The spring was perhaps the more 

 important of the two : it affected the corn crops and the hay. 

 All the crops in the United Kingdom were below the average 

 of the preceding ten years, although in Great Britain alone 

 meadow hay was a little better than usual, and hops were 



Figure 228. 

 A new model Microscope. 



Figure 229. 

 A Rhipicephalus from Australia. 



also above the mean by fully twenty-three per cent. The 

 harvest of 1912 must be classed as very deficient, and one of 

 the worst experienced for many years. 



H A R V EST WEATH ER FO RECAST.— The Meteorological 

 Office will be prepared, from June 1st to September 30th, to 

 supply forecasts of weather by telegraph, to farmers and other 

 persons desirous of receiving' them, upon payment of the cost 



of the telegram. The forecasts 

 are drawn up each week-day, 

 at 2.30 p.m., and refer to the 

 probable weather during the 

 fifteen hours from 6 a.m. to 9 

 p.m. on the next day. A note 

 as to the further outlook is 

 given when possible. Applica- 

 tions for the forecasts should 

 be sent to the Director, Me- 

 teorological Office, South Ken- 

 sington, London, S.W. 



MICROSCOPY. 



By F.R.M.S. 



A NEW MODEL MICRO- 

 SCOPE. — Figure 228 repre- 

 sents a new pattern microscope, 

 designed by Mr. E. Leitz, which 

 combines in itself features of 

 both the English and Conti- 

 nental models. There is a 

 tripod base which gives rigidity 

 in the horizontal as well as in 

 the vertical position. A curved 

 limb allows of additional work- 

 ing space on the stage, which is 

 of the square fixed type, though 

 a detachable mechanical 

 arrangement may be added. 

 The sub-stage has centring 

 screws controlling the conden- 

 ser sleeve which is of the 

 standard gauge of the Royal 

 Microscopical Society, while 

 the fine adjustment is of 

 the type originally introduced into the Leitz Continental 

 Microscopes and consists of a cam and worm screw 

 continuous motion. 



AN AUSTRALIAN TICK.— A short 

 time ago two small " insects " were sent to 

 me by a friend in Devonshire, who said 

 they had been found on the dress of a 

 child, whose mother, being unable to rec- 

 ognise them, feared they might be some 

 species of Citnex, and was anxious to 

 know if this was so, and where it was 

 likely they came from. On placing them 

 under the microscope I saw at once that 

 they were Ticks, but were so flat and 

 so dry that I concluded they had died 

 of starvation, and had been dead a long 

 time. They measured -18 inch in extreme 

 length and were lemon - coloured, with 

 purple-brown markings and spots. After 

 careful examination and comparison with 

 the figures and descriptions given by 

 Neumann in his " Revision of the Ixodes," 

 I determined them to belong to the 

 genus Rhipicephalus, and therefore cer- 

 tainly not British ; but as to species they 

 did not exactly agree with anything figured 

 either by Neumann or by any other authority consulted. 

 Having only two specimens I was unwilling to dissect more 

 than one, and having detached and prepared its capitulum I 

 was successful in this instance in getting a clear view of the 



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