riJEhACK. V 



ii)iix>ssiblc' lor me to ust' .-my of the priutiug api»i'oi*riuti<»u lor ;i pxiblioation 

 ihat is uot directly connoctod with our current work. 



Cordially, yours, 



(Signed) Gko. Otis Smith, 



Director. 



With tills imicb bv way of explaiuition the j)i'c.seiit writer feels that 

 no apologies are necessary. The compilation has been carried on at 

 odd times, the manuscript in some instances lying a full year with- 

 out being touched. Naturally, much desired information is wholly 

 out of reach. The leading participants in these surveys have for the 

 most part gone over to the majority, and the written and published 

 residts are lacking in many interesting particulars. Undonbtedly a 

 search through State records would have broiight to light more data 

 legarding expenditures, but no fluids have been available for the 

 })urpose, and the utility of greater detail is perhaps questionable. It 

 has been the write?''s custom, in all cases where it was necessary or 

 seemed desirable, to send the manuscript to those now in charge of 

 surveys in the individual States for such information as was avail- 

 able. He takes this opportunity to acknowledge his indebtednes-^ 

 jiud express his thanks for the aid thus afforded. 



ApiuL, 1907. 

 SuppLK.MKNTAL XoTE. — It was the original intention to i)ring this 

 history down to a date not later than 1885. In but few instances 

 has this limit been passed. Any seeming desirability of so doing 

 has been anticipated by the i)ublicatioii of Bulletin 4^,") of the United 

 States Geological Survey in 1911. 



G. P. M. 



