LETTER TO THE GOVERNOR. 



To His Excellency, Samuel Merrill, Governor of Iowa. 



Sir :— I have the honor of laying before you my report embracing the greater 

 part of the results of the labors of the State Geological Survey performed by 

 myself and under my direction during the years 1866 to 1869 inclusive. The 

 work was undertaken and prosecuted during the first two years with a view to its 

 full completion, but by the act of the Twelfth General Assembly, I was required 

 to " complete the Geological Survey of the State on or before the first day of 

 January, 1870, and to prepare a full and complete report of the said Survey, 

 accompanied by such maps and drawings as may be necessary to illustrate the 

 same, and transmit them to the Governor, who shall lay a copy of such report 

 before the next General Assembly." 



The work of only a general reconnoissance has been so great that it bas been 

 impossible to fulfill this requirement, and as that fact was anticipated and so 

 stated in my report to your predecessor, Governor Stone, and by him laid before 

 that General Assembly, I have felt obliged to regard the clause just quoted as a 

 direction to discontinue the work at the time designated. I have therefore made 

 arrangements for the employment of my time, in professional duties, at the State 

 University from and after the close of the presjnt year. This explanation is 

 made for no other purpose than to account for the incomplete form in which the 

 report is now presented. 



Although it is believed that the report, as herewith presented, contains much 

 material of great practical value and scientific interest, as well as a nearly com- 

 plete general view of the geology of the State, it comprises only a part of the 

 whole work to be done. Besides the matter more or less thoroughly digested 

 and presented in this report, the Survey and its different members are in posses- 

 sion of much other valuable matter, the results of uncompleted observations, that 

 is yet too imperfect for publication. This will necessarily be entirely lost unless 

 the observations are completed. Again, a very important work is now arreste 

 in the very midst of its usefulness. This is the detailed examination of th 

 Lower coal-measure formation, which is known to contain far the most important 

 part of the coal of the State. These observations could not have been intelligibly 

 made before, by omitting others that have been made, because they must be 

 based upon more general observations previously accomplished. 



It is especially desirable that this unfinished work in the coal-field and 

 elsewhere should be completed, and the results embodied in this report before it 

 is published. A small appropriate i only, in addition to what now remains 



