GEOGRAPHY OF NORTH AMERICA. 233 



was simply due to the persistent use of pine plank in walling 

 the wells. Stone having to be brought from a distance, the 

 early inhabitants have naturally taken the most available 

 timber; and since the drift in which the wells are sunk is a 

 tight clay, the decay of the sap and pitch of the wood has 

 been confined to the water, instead of being carried away by 

 easy drainage and gravelly subsoils. 



This by no means exhausts the number of states in which 

 surveys of one kind or another principally geological are 

 in operation. Alabama, Georgia, Mississippi, North Caroli- 

 na, and Tennessee, in the south ; Indiana, Michigan, Missouri, 

 New Jersey, Wisconsin, Rhode Island, and perhaps Kansas, 

 in the north all have persons employed with a larger or 

 smaller force, with or without pay, making regular or oc- 

 casional reports to legislatures or boards of agriculture. 

 Probably the number could be increased. And surveys on 

 a somewhat extensive scale have just been completed in 

 New Hampshire, Ohio, and Illinois. In most cases, how- 

 ever, these surveys now in progress have mainly a local in- 

 terest; and I have not, therefore, attempted to obtain special 

 information concerning them. 



There have also been a few private explorations of some 

 interest; although during the past year comparatively little 

 lias been done excepting by the Peabody Museum of Archae- 

 ology at Harvard College. Under the auspices of this new 

 institution, Dr. E. Palmer spent ten months in Southern Utah 

 and Northern Arizona exploring the ancient mounds. These 

 are not such as have been used for burial, but appear to be 

 formed by the successive ruins of mud -houses; one house 

 being built upon the levelled heap which the ruins of an 

 earlier one furnished, and, in its turn, giving place to an- 

 other, when the first has been levelled by atmospheric agen- 

 cies. They are therefore mounds of residence, or ancient 

 dwelling-sites; and a considerable variety of curious pot- 

 tery has been found in them. Similar pottery was found by 

 Dr. Palmer in some rock-caves in the same region; and both 

 are probably to be referred to the old Pueblo race. Dr. 

 Palmer also made zoological and botanical collections of 

 considerable interest, coming as they do from regions sel- 

 dom visited by naturalists, discovering a number of new 

 plants and insects. He has recently gone, in the interests of 



