12 Mr. R. P. Greg on a new Meteoric Iron from Chili, 



I have employed two, of unequal dimensions. The axes of 

 the greater are 10^ and 7 inches in length, and in it points, 

 spheres, and discs can be introduced. The axes of the smaller 

 one arc 4i and 3 inches in length. For most experiments the 

 latter is sufficient, and besides this, it possesses the great advan- 

 tage of being exhausted, to a few lines of pressure, by means of 

 a few strokes of a good air-pump. 



I have also employed an extra plate, such as is furnished with 

 most air-pumps, but modified so as to suit the institution of 

 electric experiments in a vacuum. A glass disc is cemented 

 upon the brass disc ; in both two holes are made, in which 

 two thick copper pins are fastened so as to be air-tight, and 

 yet not to touch the bi'ass ; these pins project above and below, 

 are 6 inches distant from one another, and their extremities are 

 provided with holes and clamp-screws, so as to receive the 

 necessary connecting wires. By means of the glass disc, many 

 experiments can be made which it would be impossible to 

 make in the egg ; for upon it several kinds of apparatus can be 

 placed, and over all a bell-shaped receiver can be inverted in 

 order to surround all by a vacuum. The arrangement is also 

 more air-tight than the egg, as it contains no stuffing-box, which, 

 however, should motion be required during the experiment, can 

 be added to the glass receiver. 



[To be continued.] 



II. 1. Desc?-iption of a neiv Meteoric Iron from Chili, contain- 

 ing Native Lead. By R. P. Greg, Esq^' 



2. Fall of a large mass of Meteoric Iron at Corrientes in South 

 America^. 



1. A SHORT time since I purchased a mass of meteoric 

 -L\. iron weighing upwards of 17 lbs. ; its shape was irre- 

 gular and cup-like, considerably convex or hollowed out on one 

 side, and the external surface more or less covered with small 

 angular and conchoidal projections. It was found by Mr. 

 Greenwood, Reporter of Mineral Properties, on the 26th of 

 February, 1840, on the desert of Tarapaca, 80 miles N.E. of Tal- 

 cahuaxo, and 46 miles from Hemalga ; and was afterwards ana- 

 lysed, in 1853, by Mr. George Darlington, of the Museum of 

 Practical Geology, with the following results : — 



* Communicated by the Author. 



t From the Liverpool Literary and Philosophical Society's Journal. 



