135° 
THE GEELONG NATURALIST. AX 
writer's powers, the nearest resemblance he can frame to any 
other phenomenon on the earth's surface being the “Sea of 
Ancient Ice,” described by Capt. Nares, where the waves 
seemed to have frozen while still heaving. 
We can imagine the Rises, a district of about a hundred 
square miles, boiling with great violence—a veritable witch’s 
cauldron—when suddenly a safety valve opens in one of the 
surrounding craters, and the boiling mass is left to solidify. 
As could be expected from its appearance, the surface is 
very porous, and the soil —what there is of it—is very fertile, 
being decomposed volcanic matter, coloured red or chocolate 
by red oxide of iron. 
This porosity renders the Rises one of the finest water 
catchments in the colony, but not a surface catchment. 
Anywhere throughout the Rises, if wells be sunk, the purest 
water can be obtained in abundance. From one spring 
issuing in limpid flow from therocky sides of a glen, enough 
water could be secured to supply a large town. In fact it 
was proposed a few years ago to tap the Rises for a supple- 
mentary water supply for Geelong. This same porous 
nature, but on a larger scale, is visible in the several caves 
found here. Near Mt. Porndon, the central feature of the 
Rises, is a cave entered by a narrow opening among the ferns. 
The visitor provides himself with an armful of bracken, 
and after venturing in as far as the dim light will allow, 
makesa bonfire. The flames do not light up any brilliant 
stalactites, but disclose an arched roof of bluestone about 3o 
feet high, which gradually descends till, at a hundred yards 
distance, it approaches the floor. 
Some present may remember that Pomborneit guano was 
on the market several years ago, and although offered at a 
higher price than the iniported, it was very soon all disposed 
of. It was from this cave that guano was produced. It was 
evidently the excreta of a carnivorous bat-like animal. The 
guano of Peru being the product of sea-birds, possessed 
more phosphate, but it has been for centuries exposed to wind 
and suh, while this guano was preserved from the weather 
in the recesses of the earth. Unfortunately the deposit was 
limited in extent, and is now exhausted, not even a specimen 
being left. 
(To be continued.) à 
