96 BOARD OF AGRICULTURE. 



Afteenoon Session. 



The Board was called to order at two o'clock. Mr. Baker, 

 of Marshfield, in the chair. 



BOWLDER ROCKS: THEIR PRgBABLE ORIGIN AND HISTORY, 

 AND THEIR USE IN THE CONSTRUCTION OF DWELLINGS. 



BY DR. JAMES K. NICHOLS. 



Gentlemen : — I wish to say a word in a preliminary way 

 regarding this lecture. I have to speak to you this after- 

 noon under disadvantages which, I fear, will render the 

 service unsatisfactory to you and to myself. I have not fully 

 recovered from recent indisposition, and I have not been able 

 to give the subject that careful consideration which one in- 

 volving scientific statements and facts demands ; and also, I 

 have been prevented from writing out the lecture, as it was 

 my intention to do. Therefore, the hour must be spent 

 in a familiar "talk" (for I can call it nothing else) upon 

 bowlder rocks, their probable origin and history, and their 

 use in the construction of dwellings. 



I have selected this subject because I am certain there 

 exists among husbandmen a desire to know somethino: of the 

 history and nature of the rocky masses with which they are 

 brought daily and hourly in contact in the cultivation of their 

 fields ; and further, I desire to call attention to the desirability 

 of using the bowlder rocks in the construction of buildings in 

 the place of wood, which has been almost universally used in 

 all parts of the country ever since its first settlement. 



Now, in relation to the origin of rocks, a consideration of 

 this subject, of course, carries us back to a very remote 

 period of time. It is suificient for me to say, that rocks, like 

 other inorganic substances upon our planet, have been at 

 some time in their history in a volatilized condition. In 

 fact, we may say that every rock and every mineral sub- 

 stance upon our earth has existed in the form of vapor ; and 

 I think Ave may go still further, and say of rocks and all ele- 

 mentary substances, that they have once existed in still more 



