On Artesian Wells, 79 



titute of organic remains. This forms the most elevated part of the 

 country, and extends over a large portion of Clark County, affording a 

 poor soil, of which the prevailing timber is the long-leafed pine (Pinus 

 palustris) associated with dwarf oaks. This sandstone often affords 

 hollow cylinders several inches in diameter, and from one to three feet 

 long, the cavities of which frequently contain a red ochre (oxide of iron), 

 sometimes used by childreji as a pigment. 



Bones of the Zygodon have been seen in Washington County, Missis- 

 sippi, and from thence they have been found in several places as far east 

 as Clariborne, on the Alabama River. Judge Creagh relates, that when 

 he first moved to Clark County, about twenty years ago, these bones, 

 consisting mostly of large vertebrae, were so numerous as seriously to in- 

 terfere with the tillage of some of his fields ; and hence they burned large 

 quantities of them in the fires of their log heaps. At this time scattered 

 vertebr», generally much broken and wanting processes, are lying on 

 the surface of the ground in almost every field of Judge Creagh's and 

 the neighbouring plantations. Among these no head or part of one is 

 known to have ever been seen, except those parts which Dr Harlan de- 

 scribed, and these in our possession. The reason of this is, that the jaws 

 were hollow and composed of a thin plate or plates of bone filled with 

 animal matter ; and when this matter contained in the cavities was de- 

 stroyed, the exterior plates were easily broken. It may be well to men- 

 tion that Clark County is situated between the Alabama and Tombigbee 

 Rivers, about one hundred miles north of Mobile. 



For a knowledge of this huge being of a former and remote age, the 

 public are greatly indebted to Judge Creagh, who kindly assisted and 

 furnished hands to assist in digging out the bones^ and provided mate- 

 rials to make the boxes for containing them. He also had them con- 

 veyed to the Tombigbee River (twelve miles), after which he refused to 

 take any compensation from one who went to his house a stranger, with- 

 out even a letter of introduction. The skeleton was sent via Mobile to 

 New York, where it is at present in fourteen large boxes, some few of 

 which have been opened to gratify the curiosity of several scientific 

 gentlemen, who are ready to testify that we have a unique and veritable 

 skeleton of the Zygodon.* 



On ArtesianWells. By Admiral Sir David Milne, G.C.B. 

 Communicated by the Author. 



The theory of Artesian Wells, maintained by Buckland, 

 Arago, and other first-rate authorities, rests on a circumstance, 

 which seems to me liable to some doubt, and which I now mean 

 briefly to consider, namely, the necessity of the water which 



* Am erican Journal of Science, April 1843, p. 409. 



