258 Dr. J. W. Webster on St. Michael 
found to be much more porous and vesicular than any lava 
I had previously seen. The cells were nearly perfect 
spheres arranged in concentric circles, and most of them 
were large enough to contain a pea. They were not visi- 
ble, however, till the stalactites were broken, being covered 
with a smooth and hard crust. The partitions between the 
cells were less than the sixteenth of an inch in thickness, 
and had an imperfect glimmering lustre on the fresh frac- 
ture. Most of them contained a loose brown, earthy mat- 
ter, probably the result of partial decomposition. ‘The sta- 
lactites, externally, have a dark iron grey colour, sometimes 
passing to black, and they are deeply channelled in a longi- 
tudinal direction. ‘They occur of all sizes, some of them 
are less than an inch in length, while others exceed a foot. 
Their diameter is not less variable but never exceeds six 
inches at the thickest part. ‘Those which were about a foot 
in length, were usually fram one to three inches thick.” 
When these stalactites were broken, water fell from them, — 
but externally theyjweredry. The attraction of the volcanic 
rocks of this island for moisture is observed by the author to 
be very great and to this he attributes in a good degree, the 
fertility of these regions: the same remark holds true of 
other volcanic regions, and even of trap countries although 
in this respect they are less remarkable. 
“The difficulty of penetrating to the last apartment of the 
cavern, was by no means inconsiderable, and for the last 
few yards, we were obliged to creep upon the bottom, and 
advance with the utmost caution, while the sharp points of 
hundreds of stalactites were in contact with our clothes.” 
Some of the circumstances noticed in the lava of these cav- 
erns, are curious, &c. throwing light on the manner in which. 
they may have been formed, the lava appearing like melted 
lead thrown into water—the walls “‘ in some places seem to 
be covered with petrifactions or vegetables, and shrubs, re- 
taining the most perfect resemblance to their originals,” 
some specimens resembled bunches of grapes partially flat-. 
tened, and some were like ‘‘ coarse lace.” 
Chap. XII. “ Geology of St. Michael continued—Erup-. 
tions from the sea.” In addition to the facts which the author. 
examined in person, as to the structure of the rocks, &c. he. 
has given the details of the recent volcanic eruptions, all. 
“proving these islands to be “* among the most recent forma- 
tions of our globe,” but we have not room for extracts from this 
