Chap. 29.] Wty Steel Jlrikes Fire with Flint. i6| 



the friction which feparatcs them from the mafs, fo 

 as to difpofe them to inflammation. Thefe particles 

 are feldom larger than the two hundredth part of an 

 inch in diameter, and when examined by a magnifier, 

 are found to be brittle, of a greyifh colour, refembling 

 the fcales of burnt iron. Another proof of the inflam- 

 mability of iron is, that iron wire, heated at one end, 

 and plunged in a jar of oxygen gas, burns with con- 

 fiderable rapidity, and with a very brilliant flame. 



Iron is by far the moft abundant in nature of all 

 the metals. It is not only contained in almoft every 

 foffil, particularly in thofe which are coloured, but 

 -makes a part of vegetable and animal matter. With 

 refpect to the ores of iron, however, as they are very 

 numerous, it will be neceffary only to notice thofe from 

 which the metal may be extracted with advantage. In 

 thefe ores iron exifts either in the metallic or calciform 

 ftate, or mineralized by different fubftances. 



Native Iron is known by its colour and malleability. 

 It is very rare, and is only found occafionally in iron 

 mines. Some naturalifts think that thefe apparently 

 native fpecimens of iron have been produced by art, 

 -and have been buried in the earth by accident. 



In the Philofophical Tranfaftions for the year 1788, 

 % vol. Ixxviii. is an account of a mafs of native iron, 

 weighing by admeafurement about three hundred quin- 

 tals, which lies in the midft of a wide extended plain, 

 in the middle of South America, in latitude 27" 2&' 

 fouth, and at the diftance of feventy leagues eaft, one 

 quarter fouth, from the hamlet of Rio Salado. It has 

 the appearance of having been liquid, and bears the 

 impreffion of human feet and hands of a large fize, as 

 well as of the feet of large birds common in that 

 country. The extraordinary fad of fuch a mafs of 



Vot. II r M iron 



