200 



KNOW LEDGL. 



May. I'll. 



bl.ickc'iicil bulb tliL'iiiiometor at Gii'onwicli. In the .shade- 

 on the gras.s, a second thermometer stood at 52"K. at the 

 beginning and end, and fell to 44° at 12.20 p.m. — a drop of 8°. 



The very slight easterly wind, after veering to the south, 

 dropped to a dead calm at niid-eclipsc, again rising afterwards 

 to its former strength. 



Birds were unafl'ectcd by the phcnomenun. singing loudly at 



nooo as usual, but tulips in the sun, which were open prior to 

 the eclipse, closed right up before the niid-eclipsc and were 

 again open by the end. Those in the shade were unaficcted. 

 So far as the intervals between my photographs allowed, I 

 kept a watch for other phenomena, shadow-bands, and so on, 

 but nothing was seen. A white sheet was spread on the 

 ground for this purpo.se. 



S()I..\K DIsriRD.WCE.S 1)L'RI.\(; M.AKfll. 1912. 

 By FRANK C. DENNETT. 



M.\KCll has a more interesting record than the two previous 

 months. Only on twelve days has Ihc disc been apparently 

 i|uitc free from disturbance, ihougli on seven others only 

 faculae were seen, but a spot group, the first this year, was 

 visible on the remaining twelve. The longitude of the central 

 meridian at noon on the 1st was 86°5l'. 



1.— A bright faculic disturbance within the eastern limb, on 

 the morning of .March 7th, was seen to contain a spot about 

 fifteen thousand miles in diameter, with a bright photospheric 

 arm penetrating a long way from its north-eastern border. In 

 the afternoon this was found to be the leader of a consider- 

 able gfoup. The group was very active presenting constant 

 change. On the 11th, a pore easily seen at 9.30 a.m., could 

 not be found a few minutes later. At 2.30 p.m. the spectro- 

 scope showed considerable activity present. The axis of the 

 group showed a decreasing angle with relation to the solar 

 equator as the group progressed across the disc, and on the 

 18th only the leader remained visible, much decreased, amid 

 a faculic disturbance, the latter being still visible next day. 

 On the 9th, 10th and Htli. the inner i-xh^e of the penumbra 



was noted as being brightly fringed. It will be noticed that this 

 group is in the same position as the little group No. 41 in the 

 record for December, 1911. 



A faculic disturbance was recorded near the south-western 

 limb, on March 3rd, and so near longitude 140°. On the 5th. 

 a similar area was seen near the same limb, and therefore 

 near longitude 95°. On the 6th and 7th. a faculic district in 

 longitude 310°, N. -latitude 2cS % was advancing from the north- 

 eastern limb. On the 16th a small bright Unot in longitude 

 180°, S. -latitude 66°, was noted. On the l.Sth. a faculic dis- 

 turbance was seen nearly in the same longitude as the spot 

 group, but much farther south. On the 22nd. a bright knot 

 was within the eastern limb, near longitude 90^. On the 24th, 

 a faculic district was nearing the north-western limb, and 

 on the 27th and 28th, a small facula was near the western 

 limb, longitude 170\ S.-latitude 7°. Two of these will be 

 found marked on our chart. 



The chart is constructed from the combined observations 

 of Messrs. J. McHarg, .'\. A. Buss. E. E. Peacock, W. H. Izzard, 

 and the writer. 



DAY OF .MARCH. 



10 CO 30 W a> 60 70 a> 90 IOC no l?0 I30 ItO ISO ItO m ISO I90 200 SIO 2Z0 Z30 SKI 250 ISO 270 260 290 300 310 320 330 340 iX 3(0 



RIAIKW.S. 



ARCHAEOLOGY. 



The History of Fire-Makiiifi. — By Edward Bnnvtci.i,. 

 24 pages, 48 illustrations. 9-in. XS^-in. 

 (O. E. Janson & Son. Price 1/- net.) 

 That the interest and value of a publication are by no means 

 proportional to its size is shown by Mr. Bidwell's little book. 

 For very many years Mr. Bidwell has collected and studied 

 the various methods of obtaining fire, and in 1910 he showed 

 a representative series of specimens and illustrative pictures 

 in the science section of the .-Vnglo-Japanese Exhibition. So 

 few, however, of the catalogues, containing a description of 

 these, were available that many of those who would have 

 highly valued the synopsis of Mr. Bidwell's researches were 

 unable to secure a copy. Now the difficulty is removed, for 

 Mr. Bidwell has reprinted the pages from the catalogue, with 

 the addition of some illustrations made from his specimens for 

 Mr. Miller Christy. The frictional methods which at the 

 present time are practically confined to native races first 

 come in for attention, then casts of an iron pyrites 

 nodule and a flint flake found in a British barrow by Canon 



Greenwell, as well as photographs of two nodules of iron pyrites 

 used instead of flint and steel in a tinder box in SulTolk until 

 about 1827. Passing over flints, steels, sulphur-tipped 

 matches, tinder and tinder boxes, we come to the fire piston, 

 burning glass, and the electrophorus. The early chemical 

 methods, which include the first matches and ways of getting 

 fire before these were produced, complete the series and are 

 possibly the most interesting, generally speaking. 



Arrangements for bringing a sulphur match or a taper into 

 contact with semi-oxydized phosphorus and then with the air 

 are apparently the earliest and go back to the end of the 

 eighteenth century. The details of Lorentz's electro- 

 pneumatic lamp were taken from the Patent Office records 

 of 1807, and in this, hydrogen gas was ignited by means of an 

 electric spark. Pyrophorus was finely-di\ided carbon which 

 ignited upon exposure to the air. The instantaneous light 

 box was introduced into England in 1812. In this, chlorate 

 of potash matches were brought into contact with asbestos 

 soaked in sulphuric acid. Dobereiner's hydrogen lamp 

 depended upon the fact that spongy platinum becomes 

 incandescent when gas is allowed to impinge upon it and 



