TRANSACTIONS OP THE SECTIONS. 85 



the salubrity of some winds as compared with others. At all events, the experiments 

 lie had intended to have brought before the Section demonstrated that oxygen, when 

 in this state of induced polarity, combines with the noxious organic impurities of the 

 atmosphere, and converts them into carbonic acid. It would also be evident that the 

 adventitious electricity of a thunder-storm could have but small share in producing 

 the amount of polarized oxygen or ozone required for the purposes of nature. But 

 the ferruginous suboxide was not the only one that exercised this important function, 

 as several other metallic suboxides, which he enumerated, partook of the same power, 

 though in less degree. Peroxide of iron (ordinary rust), on the other hand, or metallic 

 iron, was perfectly inert. In short, the suboxides of all magnetic metaU exereised 

 this power, in degree; whilst those that belonged to diamagnetic metals, such as the 

 oxide of tin, not only did not do so, but actively exerted an opposing action—thus 

 realizing ozone on the one hand and anti-ozone on the other. He also found that 

 several gum resins and tars exercised a similar though feebler power over oxygen. 



The author gave an account of a new compound magnetic body which he had 

 succeeded in making, to enable him to carry out the purification of water on a large 

 scale. Though the magnetic oxide he had obtained from the white carbonate of iron 

 was very effective, yet it had a tendency to be reduced to fine powder by attrition. 

 He became apprehensive therefore that this circumstance might ultimately interfere 

 with the rapidity of his filtering operations. This led him to seek some mode of 

 procuring an equally effective though less friable body. After various experiments, 

 he had succeeded beyond his anticipations. By very simple means, he had obtained 

 a magnetic body combined with carbon from the hitherto refractory Cumberland 

 haematite. This new compound body, which is thus added to metallurgical chemistry, 

 consists of iron, oxygen, and carbon — an equivalent of each ; its atomic number is 

 therefore 42. Specimens of it were exhibited to the Section. It appeared very hard, 

 and when polished had a black metallic lustre. It is highly magnetic, and was said 

 to be as incorrodable as gold or platinum. Its purifying powers were stated to be 

 very great. It can be manufactured cheaply. Mr. Spencer, as its discoverer, had 

 named it Protocarbide of Iron. He stated that it was not always necessary in practice 

 to have an equivalent of carbon combined with the oxide, as a smaller proportion con- 

 ferred the requisite hardness, in which case it was prepared more quickly ; but, in 

 making, if kept at a low red heat along with uncombined carbon for a longer time, 

 the combination took place in equivalent proportions. 



Notes on a Gold Nugget from Australia. By Prof. J. Tennant, F.G.S. 



Gold was found first in quantity in Australia in the year 1850 ; this consisted chiefly 

 of small scales and lumps obtained from various washings, and only amounted alto- 

 gether to a few pounds troy. 



In 1851 the nuggets began to be received; the first of any size is in my hand; 

 it contains about 9 ozs. of gold mixed with quartz, being a waterworn specimen. £50 

 was asked for it. They then began to arrive in sizes varying from one to five and 

 six lbs. weight. 



1852. — John Bull Nugget was exhibited to the public in London for sometime; it 

 weighed 45 lbs. G ozs.; when melted, it yielded gold to the value of £2500. 



1853. — A piece of quartz containing gold, brought over in the ' Sarah Sands,' was 

 melted in July, and yielded gold to the value of £5532 7*. 4cl. 



1854-57. — Various specimens, varying from £1000 to £2000 in value. 



1858. — The large nugget called the " Blanche Barkly Nugget," weighing 1743 ozs., 

 nearly 146 lbs., was melted August 4th by Messrs. Brown and Wingrove, and yielded 

 gold to the value of £6905 12s. 9d. ; only about 22 ozs. of impurity. 



This was exhibited several months at the Crystal Palace, Sydenham. 



The " Welcome " nugget, of which the model before us shows the exact size, was 

 brought over in the ' Salffolk,' and received in London in June last. It was found 

 June 11, 1858, at Bakery Hill, Ballarat. The weight is 2217 ozs., or 184 lbs. 9 ozs., 

 and it is now in the possession of Messrs. Dangleish, White, and Hankey, of Great 

 St. Helen's, Australian merchants. I expect it will be melted in the course of next 

 week. 



