THE FIRST VISIT 
119 
compartment is a small square iron door, like those 
through which food is passed in model prisons to 
the inmates of the cells. This door, in the case of 
the poisonous snakes, is set high above the ground, 
and is reached by a set of steps which travels on 
a rail. It is therefore possible to observe the crea- 
tures’ movements while the player of the music is 
out of sight below. 
The “ dweller on the threshold ” of the snakes’ 
home is the monitor lizard, an active and formidable 
saurian some 5 ft. in length, whose watchful habits 
were said to give warning of the approach of the 
crocodile. It did not belie its reputation for watch- 
fulness, for the instant that it heard the sounds of 
the violin through its opened door, it raised its head, 
and stood alert and listening. Then the forked 
tongue came out and played incessantly round its 
lips ; soft, slow music followed, and the lizard became 
quite still, except for a gentle swaying of the head 
from side to side. Two groups of black snakes from 
the Robben Islands next claimed our attention, and 
gave some evidence of the way in which the physical 
conditions of the moment affect the sensibilities of 
these creatures. In the first cage, they remained 
absolutely torpid, looking exactly as if carved out 
in polished ebony. In the next, the heads were raised 
at once, the forked tongues played, and at a sudden 
discord each snake’s head started violently back. 
Nor was this quick repulsion caused by any sudden 
movement of the bow, for the player was invisible. 
