464 



NATURE 



[December 23, 1915 



stone. This is particularly the case with zircon, a 

 mineral to which Sir Arthur Church had devoted much 

 study, though unfortunately he had not completed his 

 observations or prepared them for publication. Of 

 this species there are sixty-nine faceted stones, rang- 

 ing from colourless to various shades of red, brown, 

 yellow, green, and even sky-blue. Other strong suites 

 are of tourmaline, garnet (including a fine example of 

 spessartite, the rare manganese-garnet), spinel, opal, 

 corundum, chrysoberyl, and peridot. Examples of 

 rarer species represented In the collection are phena- 

 kite, andalusite, and enstatite. 



By means of a submerged chamber, provided with 

 large glazed apertures and entered through a 

 tube attached to the well of a specially con- 

 structed barge, the brothers G. and E. William- 

 son have devised a means whereby they can 

 take kinematograph pictures of marine animals 

 and make surveys of the ocean floor, down to a depth 

 of as much as 30 fathoms. The complete success of 

 their ingenious method was demonstrated at a private 

 view, given on Tuesday afternoon, at the Philharmonic 

 Hall, London, and the exhibition will be open to the 

 public in a few days. Some remarkable pictures, 

 taken in the Bahamas, were thrown on the screen, 

 showing " snappers " and other fish which haunt coral 

 reefs, divers gathering sponges, sharks attracted by a 

 dead horse suspended in front of the observation 

 chamber, and, finally, an encounter with a shark by 

 one of the inventors of the apparatus. Pictures taken 

 at night, by means of several Cooper-Hewitt mercury 

 vapour lamps, were also shown. The inventors claim 

 that their apparatus will enable treasure to be raised 

 from vessels sunk in shallow water with far more ease 

 than hitherto, since they have devised a means of push- 

 ing the arms through special apertures, enabling the 

 diver to seize objects seen through the observation 

 chamber. Another and very real advantage of this 

 method of submarine work is that the operator is enabled 

 to remain at work for long periods without suffering the 

 discomforts inseparable from the ordinary means cf 

 diving. From a spectacular point of view it Is to be 

 hoped that the Inventors will be able further to im- 

 prove on their chamber, for It Is distinctly distracting 

 to see the floor of the ocean heaving to slow music 

 while fishes of various bizarre shapes and colours dis- 

 port themselves for our edification. This movement 

 is at present inseparable from the rise and fall of the 

 barge with the swell. If the chamber could rest on 

 the bottom, by lengthening the tube, this motion would 

 be avoided. 



The director of the Meteorological Office Informs us 

 that during the last three months a number of auroras 

 have been reported by Mr. G. A. Clarke, the observer 

 at King's College, Aberdeen. His latest report on the 

 subject refers to a fine display commencing about 

 6 p.m. on December 6, and lasting until after mid- 

 night. It seemed to attain Its maximum between 

 8 p.m. and 10 p.m. About 9.30 p.m., according to 

 Mr. Clarke's report, a very extensive and bright glow, 

 topped by a narrow arch, stretched from N.E. right 

 round to W. Above this arch at an elevation of 60° 

 from the horizon were some streamers, and a series 

 NO. 2408, VOL. 96] 



of very fine rapid pulsations of light of a pale green 

 white to lavender or pale rose tint. The arch and 

 glow were pale greenish, and gave sufficient light to 

 form faint shadows of buildings, similar to what occurs 

 in faint moonlight. This aurora was accompanied, as 

 has been the case with most of the auroras reported 

 recently by Mr. Clarke, by a good deal of magnetic 

 disturbance. At Kew the curves were considerably 

 disturbed during the whole afternoon of December 6, 

 and up to 4 or 5 a.m. on December 7. The total range 

 of declination was about 49', and that of horizontal 

 force about 1707 (17=1x10-* C.G.S.). The most 

 outstanding declination movement at Kew took place 

 between 9.55 and 11.40 p.m.; during this time the 

 needle swung 28' to the east, and returned practically 

 to Its original position. The most notable horizontal 

 force change was a rise of 150 7 between 10.20 and 

 10.45 P-J^- These changes. It will be noticed, occurred 

 somewhat later than the hour when the aurora at 

 Aberdeen was most brilliant. 



A USEFUL popular account of fleas by Mr. F. C. Bis- 

 hopp has been Issued by the United States Department 

 of Agriculture (Bulletin 248). The life-history of these 

 familiar Insect parasites is sketched, and their Import- 

 ance as carriers of bubonic plague and other diseases 

 Is duly emphasised. Practical measures for exter-^ 

 minating fleas and gaining protection from their 

 attacks in infested localities are not forgotten ; for 

 example, a man sitting in a room Inhabited by the 

 insects Is advised to wrap his legs with flypaper, or 

 to wear khaki trousers and have them " tucked into 

 high-top shoes." 



A KNOWLEDGE of the Ilfe-hlstorles of the ecto-para- 

 sites of man is, at the present moment, of vital import- 

 ance to us all, and especially to those of our countr}- 

 men who are on active military service. We are glad, 

 therefore, to see In the Journal of the Royal Society of 

 Arts the report of a lecture on this theme by Dr. A. E. 

 Shipley, the master of Christ's College, Cambridge. 

 Herein Dr. Shipley, In his own Inirhitable way, gives 

 a brief account of the habits and habitats of the head 

 and body louse, the flea, and the bed-bug, and the 

 diseases spread by them. By way of illustrating the 

 devious ways In which these pests extend their range, 

 he remarks of CImex, the bed-bug, that it was un- 

 known to the aboriginal Indians of North America, 

 and probably, therefore, "entered that continent with 

 the ' best families ' In the Mayflower " ! Other disease- 

 bearing insects, like mosquitoes, tsetse- and other 

 biting-flies, house-flies, and bluebottles and other In- 

 sects which spoil the food of man, like flour-moths and 

 biscuit " weevils," are each in turn passed in review, 

 and their ravages explained. 



In the Scottish Naturalist for December Mr. A. 

 Landsborough Thomson continues his notes on the 

 Aberdeen University bird-marking scheme. We would 

 suggest that where birds are recovered which were 

 ringed as nestlings at the same time and place it 

 would be helpful if it was stated whether they were 

 nest-fellows. A case In point occurs in Mr. Thomson's 

 notes. Two sheldrakes were ringed as nestlings at 

 Beaulieu, Hampshire, in July, 1912 ; one was recovered 



