BARTHOLOMIEU DIAS S FURTHEST EAST. IOJ 



details, especially of Duarte Pacheco's account, as his 

 " Esmeraldo de situ ( )rbis " is not available in South Africa. 

 Joao de Barros's and Manuel de Mesquita Perestrello's accounts 

 are, however, given both in the original and in translation in 

 Dr. Theal's " Records of South-Eastern Africa." 



Lime Cartridges for Shattering Rocks 



—Letters patent have recently been issued in England for a 

 lime cartridge to be used for breaking down coal, rocks, and 

 other minerals. The cartridge comprises a metal tube, which 

 is hermetically sealed and is packed with granules of quicklime. 

 Inside of this tube is another, which is perforated and fitted 

 with a non-return valve, through which water can be forced 

 into contact with the 'lime. The tube is capable of withstanding 

 a pressure of about 2,000 lb. per square inch, and produces a 

 large shattering effect upon bursting in a borehole. 



GALE'S COMET. — On the 19th September .Mr. \\ ". F. 

 Gale, of New South Wales, discovered a new comet, 1912a 1 , 

 near 6 Centauri, It was of the sixth magnitude, and was 

 travelling northward and eastward. After traversing in suc- 

 cession the constellations Hydra, Libra, and Serpens, it crossed 

 the constellation Hercules during the early part of November, 

 grazing the eastern boundary of Corona. On the 13th Septem- 

 ber a photograph of the comet taken by Mr. H. E. Wood at 

 the Union Observatory, Johannesburg, showed a tail of about 

 four degrees in length, with a shorter tail, one degree long, and 

 inclined to the other at a considerable angle. The comet had no 

 stellar nucleus, but merelv a central condensation. 



THE OXYGRAPH.' — In a recent issue of The Engineer- 

 ing Record, this appliance, which operates on the principle of 

 the Pantagraph, is described. Unlike the latter instrument, 

 however, it is not hand-driven, but is propelled by means of 

 an electric motor, attached to the head of the instrument. More- 

 over, it does not enlarge or reduce the original drawing in pencil 

 on paper, but cuts it into three-inch steel by means of an oxy- 

 acetylene torch, at a speed of six inches per minute, and is 

 capable of cutting curves and right-angled corners. The 

 mechanically propelled tracer moves at a uniform speed along 

 the lines of the pattern on the tracer table, a reproduction of 

 the design being meanwhile cut in the steel by the torch. 



