The first question for us, I said, was to ascertain how to best protect ourselves from like dangers. We then proceeded to discuss the physical conformation of our country. It is a vast table-land, situated at a great height far above the tropical and miasmatic plains, and surrounded by mountains still higher, in which dwell the remnants of that curious white race first described by Stanley. The only access to our region from the lower country is by means of the ordinary wagon road which winds upward through a vast defile or gorge in the mountains. At one point the precipitous walls of this gorge approach so closely together that there is room for only two wagons to pass abreast. We determined to assemble all our men the next day at this place, and build up a high wall that would completely cut off communication with the external world, making the wall so thick and strong that it would be impossible for any force that was likely to come against us to batter it down.
This was successfully accomplished; and a smooth, straight wall, thirty feet high and about fifty broad at its widest point, now rises up between our colony and the external world. It was a melancholy reflection that we--human beings--were thus compelled to exclude our fellow-men.
We also stationed a guard at a high point near the wall, and commanding a view of its approaches for many miles; and we agreed upon a system of bale-fires (_Bael_ fires), or signal beacons, to warn the whole settlement, in case of the approach of an enemy.
We next established a workshop, under the charge of Carl Jansen, in which he trained some of our young men in metal-working, and they proceeded to make a large supply of magazine rifles, so that every man in the settlement might be well armed. Carl is one of those quiet, unpretending men whose performance is always better than their promise; and he is a skillful worker in the metals. The iron and coal we found in abundance in our mountains. We also cast a number of powerful cannon, placed on very high wheels, and which could be fired vertically in case we were attacked by air-ships;--although I thought it probable that the secret of their manufacture would be lost to the world in the destruction of civilization. We, however, carefully housed the Demon under a shed, built for the purpose, intending, when we had time, to make other air-ships like it, with which to communicate with the external world, should we desire to do so.