Vol. 60.] 



NEW CAVE AT GIBRALTAR. 



3L 



obtained of the ' main hall,' and of the stalactites and stalagmites 

 with which it is decorated. Some of these are of considerable size, 

 and measure from 3 to 5 feet in circumference, 3 feet from the ground. 

 The hall has a width of 45 feet, and an estimated height of 70 

 at its greatest. It will be at once observed that the tloor slopes 

 westward at a considerable angle, about 20 '-. This slope, as will 

 be seen in PI. VI, fig. 1 , continues for a distance of about 140 feet 

 to a point 19 feet above sea-levei. The floor is very smooth with 

 stalagmite, and some of the fallen stalactites are firmly recemented 

 to it. The southern side of the main hall is for some distance 

 striated, as if from the action of blown sand. 



E. 



Pig. 1. — Section at Monkey's Quarry ', Gibraltar. 



&&J L 



Sea-Levell_ 



Quarry - Floor 



150 ft, 



Breccia 



_______ oreccia _ ___ jc<Jts 



t=r,& 



At this point (L in the section, PI. VI, fig. 1), the lower gallery 

 begins. This runs almost horizontally for a distance of 180 feet, 

 turning to the south-west at 120 feet : then there is a sharp dip 

 downward, and the passage becomes so narrow that it is impossible 

 to proceed very far. Fig. 1 in PI. VI shows that, as a matter of fact, 

 the end of the horizontal part of the gallery is a few inches higher 

 than the entrance, and that there is a slight rise about halfway 

 along, but this is probably due to the unequal filling-up of the 

 floor, and also to the unequal deposit of stalagmite. The mean height 

 of the floor above sea-level is about 16 h feet, and the lowest point 

 reached in the descending fissure is very little, if anything, above 

 the level of the sea. There is no standing water here or elsewhere 

 in the cave, except one or two small puddles. The sides of this 

 fissure are honeycombed in a very marked manner, to the height of 

 about 10 feet from the floor. The pittings are from 3 to 5 inches 

 in diameter, and about \\ inches deep. The sides and roof of the 

 fissure, at the point where it begins to turn down, are smooth and 

 waterworn, but the descending part, as far as could be seen, is not 

 so, except the floor, which is smooth because it is covered with 

 stalagmite. The floor has been opened at a point marked 2 on the 



