194 THE SWISS FAMILY ROBINSON
greenish-coloured body. What do you think of it?'
' That we must fly to the grotto,' I answered gravely.
' What do you think it is ?'
'A serpent—a huge serpent, advancing directly towards us.'
' Shall I run for the guns ?' he cried.
'No, no,' I answered, 'run all of you to the grotto. The serpent is too powerful to permit of our attacking him, unless we are ourselves in a place of safety.'
We hastened to gain the interior of the grotto, and prepared to receive our enemy. And we started none too soon, for he advanced so quickly, we had only just time to escape. When he reached the river bank we could see plainly that it was a huge boa-constrictor, who writhed along toward us.
He crossed the bridge, and directed his course straight for the grotto. We had barricaded the door and the windows as well as we were able, and ascended into the dove-cot to which we had made an interior entrance. We passed our guns through the holes in the door, and waited silently.
The boa came on hesitatingly, until at last he