Then I allowed my glances to return to the boats, and wondered whether those in them could see the ship.  I came to the conclusion that they could not, being by this time too far over toward the other side of the lagoon, and consequently too close in to the mangroves to be able to see over them.  I now most ardently wished that I had thought of arranging to display a signal warning them of the approach of the ship, for it would be a piece of information very useful for them to possess under the existing circumstances; but I had not, so there was no use in worrying about it.  And even as I came to this conclusion the gig, still leading, disappeared within the narrow channel giving access to the river, and was quickly followed by the other boats, until the whole had vanished.