162 Capt. Martin on Bones of the Mammoth 



soft, decayed tusk, eleven feet in length, were dredged up between Boulogne and 

 Dungeness. The bottom of the channel at the point where it was found, consists 

 of blue clay with rounded pebbles. The fishermen cut the tusk to pieces to obtain 

 some ivory fit to manufacture. A section which I procured from near the alveolar 

 cavity, is of an oval shape and measures nineteen inches in circumference. 



In 1837, while trawling between the two shoals, called the Varn and Ridge, 

 covered at low tide with twenty fathoms water, a fisherman suddenly encountered 

 a heavy mass, which proved to consist of enormous bones ; the net broke, but a 

 humerus, which I purchased, was secured. The upper articulation is wanting, and 

 that part appears to have been most decayed. It is of a very stony texture, and its 

 interior is filled with marine substances. The following are the dimensions : — 



Length from the lower condyle to the fracture 38 inches. 



Presumed original length 45 — 



Circumference at the upper part of the shaft 31 — 



Ditto, in the centre 20 — 



Ditto, around the lower part, just above the condyle 31 — 



Width across the condyles 10 — 



The Varn and Ridge lie in the mid-sea between Dover and Calais, and form a 

 line of submarine chalk ridges, extending parallel to the cliffs on each side of the 

 Channel, and trending toward the North Sea. The Overfalls and Galloper sands 

 are continuations of the same line. The flanks of all these submarine ridges are 

 steep, and there are deep gullies in the intermediate spaces, filled with patches of 

 boulders and blocks of various stones and muddy ground. Some of these masses 

 are large spherical septaria, traversed internally by veins of iron pyrites, and con- 

 sist externally of a ferruginous crust of uniform thickness. Thus these inter- 

 esting animal remains appear to repose in marine valleys in a similar manner to 

 the analogous bones on land ; and it is evident that they are thickly strewed over 

 the bed of the sea in these latitudes. They are never found on the summits of 

 the banks or shoals, but invariably in deep water in the hollows. 



At the back of the Goodwin-sands an elephant's tusk was dredged up. The 

 part containing the alveolar cavity was broken off, but its length was 78 inches 

 and its circumference 12 inches. Its curvature was equal to a semicircle, turning 

 outwards in its line of projection. The tusk was sent to a cutler at Canter- 

 bury, by whom it was sawn into five sections ; but the interior was found to be 

 fossilized and unfit for use. It is now in my possession. From the same locality, 

 I have also a piece of fossilized tree, the heart of which is changed into a beau- 

 tiful jet. 



In the early part of 1839 I succeeded in adding to my collection a perfect femur 

 of a Mammoth. It was trawled up in the North Sea, in 20 to 25 fathoms low 



