322 



A line of telegraph can be carried along the posts without any great 

 increase of expenditure. 



Besides all these unusual i-ecomm endations, the boxes are so constructed as 

 to enable them to be locked at the point of departure, so as to prevent the 

 introduction of any foreign substances of a deleterious kind while in transitu, 

 and by a simple self-acting contrivance, the load will be shot out on its 

 arrival at the battery, and a self-acting weighing machine will be attached to 

 the last post, by which the weight of the load can be correctly read off. 



Last, but not least, of the proposed advantages : — A grip has been 

 contrived by Mr. Herrich to grasp the wire at any moment, to prevent 

 accident by the sudden fracture of the line ; should a fracture occur, the 

 natviral inclination of the line would be stopped by the grip revolving upon 

 the roller on which the wire travels, and holds it firmly jammed. 



With these advantages, and the additional fact that it is believed the line 

 can be constructed at an average cost of £800 per mile, it must be evident 

 that the mining community would reap advantages from adopting this scheme, 

 which would infuse new life into its proceedings, and would resuscitate many 

 moribund companies which are being wound up, simply in consequence of 

 their inability to obtain carriage at a reasonable cost. 



The principle may be utilized for uniting any distant part of the country, 

 instead of a railway, say between Pdverhead and Helensville, a distance of 

 sixteen miles, which could be constructed at a moderate calculation, including 

 motor power, for about £10,000 ; the cost of a railway line of 3ft. Bin. gauge 

 would be £50,000, not including rolling stock. 



Art. LXIV.— 0?i the Currents, Temjjerattore, and Saltness of the Ocean. 



By W. B. Bray. 



(abstract.) 



{Read before the Philosophical Institute of Canterbury, May 4, 1870.] 



The author of this paper after describing at length the principles which have 



been established respecting the distribution of ocean currents in the ISTorthern 



Hemisphere, where they have been most fully studied, proceeds with the 



discussion of the currents in the southeim seas : — 



The Southern Hemisphere, in its geographical circumstances, contrasts so 

 remarkably with the jSTorthern, that very material differences may be expected 

 in the currents themselves ; yet the general principles are the same, in that 

 the efiect of intense polar cold produces a descending cold current, which flows 

 along the bed of the ocean towards the equator, and draws a corresponding 

 supply of warmer water to the pole, and the action of that warm current 

 on the ice produces a superficial current of cold, bu.t fresher, water from the 

 polar ice. 



In the north, the great continents approach within 15 or 20 degrees of the 



