401 Chronicles of Science. [July, 



punched steel gun-barrels is rapidly extending, and the principle 

 introduced by Messrs. Deakin and Johnson is being applied to 

 other purposes connected with machinery. Bessemer steel is now 

 beginning to be used for bridge construction, and it is stated that a 

 recent French invention is likely to be able to compete successfully 

 with the Bessemer process for the manufacture of steel. It may 

 be accepted as a general fcelief that the age of iron is gradually 

 passing away, and that in most cases where it is now employed, 

 steel will shortly take its place, as being both stronger and lighter. 



The use of water-tube boilers may be classed as one of the 

 inventions of the day, their increased strength and security con- 

 tributing greatly to their popularity. Messrs. Howard, of Bedford, 

 have recently tested their water-tube boilers to a pressure of 

 1.000 lbs. per square inch. 



It is reported that in America very heavy guns are now worked 

 entirely by steam. A centrifugal gun has been invented by Dr. 

 Steinheill, which, it is asserted, will throw from 60 to 100 bullets 

 a minute, but the power necessary to obtain that result is not clearly 

 stated. Major Palliser has been awarded 15,000/. for his pointed, 

 or ogival-headed chilled shot, and in consequence of their great 

 power of penetration experiments have lately been made of the 

 manufacture of armour-plates having a steel face welded to an iron 

 body, and of plates formed of alternate layers of iron and steel, 

 with a view to obtaining greater strength without increasing the 

 weight. 



7. GEOGRAPHY. 

 {Including the Proceedings of the Royal Geographical Society.) 



The subject which of all others has attracted the interest of not 

 only the Boyal Geographical Society, but also of all who interest 

 themselves in the annals of enterprise, is the probable fate of Dr. 

 Livingstone. Some time since Dr. Kirk wrote from Zanzibar, 

 giving a graphic and, as it seemed at the time, a probable account 

 of the murder of the enthusiastic traveller by a warlike tribe on 

 the western side of the lake Nyassa. The story was derived 

 originally from certain Johanna men who had been with Dr. 

 Livingstone, but who returned without him. Bit by bit the weak 

 points of the account came out. The tale depended upon the 

 evidence of one man, Moosa, who has proved unworthy of credit, 

 inasmuch as he has since given another version of the same event ; 

 a white man is reported to have been travelling amongst more 

 distant tribes, and Dr. Livingstone himself is said to have been 



