the Igneous Platform. 191 



the uncased part in firm lava the samples are all powders, vary- 

 ing from a medium to a very fine sand in size of grain. 



As the boring progressed below sea-level no fresh water was 

 encountered, but at various levels salt water came into the 

 well. According to the notes furnished by Mr. Howe, this 

 occurred several times between 785 and 1,000 feet, and again 

 between 1325 and 1385 feet. The significance of this will be 

 discussed later. 



List and Nature of the Samples. 

 The samples of the material met in the course of drilling 

 the well, according to the labels and description, are indicated 

 as representing the nature of the rock between specified points. 

 The distance between these points is given in the accompany- 

 ing table. Possibly each sample was taken at a certain time 

 and at a definite point, but it may have been so selected as to 

 give an average between points. In general, their homo- 

 geneous appearance indicates that if the latter is the case they 

 are fairly representative, in most of them, of the stretch of 

 rock between the given points, though in the case of the firm 

 lavas below 700 feet, which, as will be seen, show a rather 

 monotonous regularity in their appearance, the petrographic 

 study has proved in several cases that two rocks of somewhat 

 different nature are mingled in the same sample. In all, 48 

 samples comprise the collection, and the stretches which they 

 represent and their general character is briefly shown in the 

 appended table. 



List of Samples of Bermuda Well. 

 No. 1, 61 Feet. Soft white Bermuda lime-rock. 



1, 



61 



Feet. 



Sof 



2, 



110 



a 



a 



3, 



241 



a 



a 



4, 



250 



a 



a 



5, 



265 



a 



n 



6, 



286 



a 



a 





331 



a 



it 



8, 



341 



a 



a 



9, 



383- 



393 



Feet. 



10, 



393- 



480 



tt 



11, 



480- 



485 



a 



12, 



485- 



505 



a 



13, 



505- 



518 



a 



14, 



518- 



544 



a 



15, 



544- 



550 



a 



16, 



550- 



554 



a 



a u 



a u 



a a 



u a 



Yellowish brown, clay-like, powder. 



Brownish crumbling earthy fragments. 



Light brown, compact, earthy matrix 

 with calcite balls. 



Brown fragments, gray within, 

 resemble decayed pebbles. 



Brown fragments, gray within, 

 resemble decayed pebbles. 



Brown, earthy fragments. 



Brown, earthy, with small gray frag- 

 ments ; calcite balls. 



Brown, earthy, with soft gray frag- 

 ments. 



