304 ANNUAL OF SCIENTIFIC DISCOVERY. 



sound and valuable stones, the principle of the operation not being 

 then generally known. 



CURIOUS MINERAL DEPOSIT IN NEW ZEALAND. 



Ever since the settlement of New Zealand by Europeans their at- 

 tention has been daily called to the peculiarities of a kind of metallic 

 sand along the shores of New Plymouth, in Taranaki. This sand has 

 the appearance of fine steel filings, and if a magnet be dropped upon 

 it, and taken up again, the instrument will be found thickly coated 

 with the iron granules. The place where the sand abounds is along 

 the base of Mount Ejjrnont, an extinct volcano ; and the deposit ex- 

 tends several miles along the coast, to the depth of many feet, and 

 having a corresponding breadth. The geological supposition is that 

 this granulated metal has been thrown out of the volcano, along the 

 base of which it rests, into the sea, and there pulverized. It has been 

 looked upon for a long time as a geological curiosity, even to the ex- 

 tent of trying to smelt some of it; but, although so many years have 

 passed since its discovery, it is only recently that any attempt has 

 been made to turn it to a practical account ; in fact, the quantity is 

 so large that people out there looked upon it as utterly valueless. It 

 formed a standing complaint in the letters of all emigrants that when 

 the sea breeze was a little up they were obliged to wear veils to pre- 

 vent being blinded by the fine sand which stretched for miles along 

 the shore. Captain Morshead, resident in the West of England, was 

 so much impressed with its value that he went to New Zealand to 

 verify the reports made to him in this country, and was fortunate 

 enough to find them all correct. He smelted the ore first in a cruci- 

 ble, and subsequently in a furnace ; the results were so satisfactory 

 that he immediately obtained the necessary grant of the sand from the 

 government, and returned to England with several tons for more con- 

 clusive experiments. 



It has been carefully analyzed by several well-known metallurgists, 

 and has been pronounced to be the purest ore at present known : it 

 contains 88.45 of peroxide of iron, 11.43 of oxide of titanium, with 

 silica, and only .12 of waste in 100 parts. Taking the sand as it lies 

 on the beach and smelting it, the produce is 61 per cent, of iron of 

 the very finest quality ; and, again, if this sand be subjected to what 

 is called the cementation process, the result is a tough, first-class steel, 

 which, in its properties, seems to surpass any other description of that 

 metal at present known. f 



EVOLUTIONS OF AMMONIA FROM VOLCANOES. 



At the last meeting of the British Association (1861), Dr. Dau- 

 bury, in a paper on the above subject, stated that the phenomena had 

 been ascribed by Bischof to the decomposition of bituminous waters 

 by volcanic heat ; by Bunsen, to the lava flowing over herbage and 

 diseno"a<nn2 its nitrogen in the form of ammonia : and by himself, to 



cT*OO O B * < 



the direct union of hydrogen and nitrogen in the interior of the earth 

 under an enormous pressure. Now, however, that Wohler has shown 

 the affinity which subsists between nitrogen and certain of the metals 



