194 William Bavies — On the Exhumation of Omosaurus. 



the British. Museum, may possibly render a short record of its oc- 

 currence and the method adopted for exhuming and developing it 

 acceptable to the readers of the Geological Magazine. 



The Directors of the Swindon Brick and Tile Company having in 

 May, 1874:, informed Prof. Owen that many large bones had been 

 discovered and laid bare in their Brick-pit by the workmen, I was 

 instructed to proceed thither to examine and report if they were 

 desirable objects for the National Collection. On arriving at the 

 works, which are situated at the foot of Old Swindon Hill and 

 adjoining the Wilts and Berks Canal, I found exposed on the floor 

 of a newly- worked portion of the pit and at a depth of about nine 

 feet from the surface of the clay six large nodules of septaria, one 

 being more remarkable than the others, not only on account of its 

 superior size, but also that it showed here and there small portions 

 of bone protruding from its upper surface (see Plate VII.). In one 

 portion of this mass, although deeply imbedded in the stone, the out- 

 line of a limb -bone could be traced, fully four feet in length, which I 

 concluded to be a femur, and in addition, either projecting from its 

 margin or in close proximity to it, and lying undisturbed in the clay, 

 were two large pelvic bones (ischium and pubis), and six caudal 

 vertebrae having centra six inches in diameter ; processes of some of 

 these were iuibedded in the septarium, as was also one end of the 

 jDubic bone (see Plate VIII. Fig. 3) . These bones ranged along a third 

 of the marginal circumference of the nodule, which was of a flattened 

 irregular elliptical form, measuring eight feet in its longest, and six 

 feet in its shortest diameter ; the margin was thin in places, but the 

 general thickness of the nodule ranged from 12 to about 20 inches. 

 About four feet from this group of bones and upon the same level 

 was another group, which consisted of an entire humerus (Plate YIII. 

 Fig. 2), ulna and radius. The distal ends of the humerus and ulna 

 were enclosed and cemented together in a small block of septarium, 

 which had to be broken before thej'" could be removed. Subse- 

 quently, on further digging, carpal and metacarpal bones were found 

 in proximity to this group, all being parts of the same fore-limb. 

 These remains, and the vertebrge more especially, I supposed to have 

 belonged to a reptile allied to Cetiosaurus, but new to science, and 

 reported accordingly, making preparations at the same time for their 

 removal. 



The exhumation of the bones which were lying in the clay was 

 readily effected by the method already described in the pages of this 

 Magazine (see Geol. Mag., 1865, Vol. II. p. 93). But how to remove 

 from the pit this large block of stone without injuring and destroying 

 the enclosed bones was a problem, for to raise it entire with such 

 appliances as we had was impossible. Yet its safe removal was im- 

 perative in the interests of science, as I believed it contained a large 

 portion of the posterior part of the skeleton of the animal. Before 

 deciding upon any special plan of operation, and to ascertain if the 

 nodule was really compact and firm, a trench about a foot deep and 

 several feet in length was dug along its margin ; a workman was then 

 instructed to insert his pick beneath and try slightly to raise the 



