TRANSACTIONS OF THE SECTIONS. 577 



with the assistance of Professor PhiUips, Mr. Harcourt selected a 

 variety of specimens of rocks and minerals from its collection, 

 which were arranged, some in mass and some in powder, in a 

 strong deal box, the capacity of which was five cubic feet. Some 

 synthetical compositions of minerals were added, and oppor- 

 tunities contrived for the formation of others, by placing diffei'- 

 ent substances in contact, and making provision for the passage 

 of volatile bodies through materials with which they enter into 

 union. Metallic substances were introduced at different points, 

 and among different materials, both to serve as measures of 

 heat, and to furnish illustrations of the phaenomena of veins. 

 A second box of equal dimensions was chiefly devoted to the 

 purpose of placing organized substances, recent and fossil, 

 animal and vegetable, under a variety of conditions with re- 

 spect to the materials in which they were imbedded. 



The boxes were conveyed to the foundries of Messrs. Hird 

 and Dawson, at Low Moor, on the 17th of July 1833. They 

 were placed immediately under the bottom stone of the furnace 

 in the sand which supports it, and built round with fire-brick ; 

 larger pieces of various rocks, metals, &c. were placed by their 

 side, and similarly inclosed by walls of fire-brick. 



The defect most to be apprehended in this arrangement is, 

 that the heat in the position above described may not suffice 

 to produce the fusion or semi-fusion of the rocks and minerals ; 

 it is presumed, however, that the cracks of the hearth-stone 

 and the shrinking of the materials will admit such an influx 

 among them of the melted metal as will secure this object ; 

 but lest such should not be the case, Mr. Harcourt was 

 anxious to effect a repetition of the experiments in a position 

 nearer to the source of heat. An opportunity of accomplishing 

 this was afforded by Earl Fitzwilliam at his foundry at Elsecar, 

 near Wentworth House. Here, under the direction of the 

 Superintend ant, Mr. Hartop, holes were worked in the bottom 

 stone itself, and in the back wall of the hearth, to contain the 

 subjects of experiment ; the number of holes was twenty-three, 

 those in the bottom stone being about a foot in diameter and in 

 depth, whilst those in the back wall were two feet in depth and 

 six inches in diameter, worked obliquely downwards. In some 

 of these were placed crucibles of six inches in diameter, and 

 eight inches in height ; in others similar cylinders of granite and 

 limestone, hollowed out, and containing various materials, the 

 spaces round, and the interstices within, being filled with 

 powders of different kinds of rocks : in the rest the minerals 

 and organized substances were imbedded in powders of the 

 same kind, without any other receptacle than the stone itself. 



1834. 2 p 



