During the year succeeding the finishing of my submarine boat, I was taken up with many new inventions almost too numerous to mention. I enclosed another large piece of ground as a pasture for my goats, of which I had now as many as I chose to keep; in fact, I loosed many of the she-goats and kids into the woods to return to a state of nature, having more than I could attend to. From the remainder I made cheese, butter, jerked meat, etc. It may be possible that some persons have lived as well as I, but at this time I had everything that could be desired. I improved upon my ways of preserving my fruits, and from a ground-nut that I found on the island extracted a most delicious oil, which I used in all my cooking. I had by this time, by repeated breedings, brought the wild quail, that I saw when first arriving at the island, to a state of barnyard fowl, and I had their delicate flesh and eggs added to my larder. From my grapes I was able to make several kinds of pleasant light wines. In fact I had everything but companionship.
But by my temperament I could not keep still, so I must yet invent something new that would be of use to me. What I wanted most at this time was glass, plate-glass for my submarine boat, and I was determined to have it. So, with my book to guide me, at it I went. I knew that silicic acid, practically glass, was represented by sea-sand. I also knew, or rather discovered from perusal and study of my book, that this sea-sand, freed from iron, formed the base of glass. Also that silica, silicic acid, or oxide of silicon exists in great abundance in nature, being the principal constituent in rock and stone, and that crystal and quartz held it in its purest forms. This, combined with potash or soda, and subjected to a powerful heat, would, I knew, make glass, if mixed in the right proportions.
In the first place I gathered some five or six hundred pounds of the finest, purest, and whitest sea-sand that I could find. This I carefully washed in some seven or eight waters of Rapid River, till it was purified of all its salt, and then it was placed in my ore-cleansing kiln, and burned, or rather heated, to a red heat, to get rid of all vegetable matter, and then sifted through wire screens to get rid of any pieces of fuel with which it might have become charged. Having thus gotten my sand all in order, purified, and cleansed, I went with the goat team, and a handy little cart with cast-iron wheels and frame, that I had made during odd times, to the coal mine, to bring home some of the chalk there to be found, of which there were large quantities, and of a fine quality. This I brought home and reduced to a fine powder by pounding it up with hammers, and sifting it through fine sieves. I then went to work and built some large fires upon the seaside, upon which, when in full blaze, I placed large quantities of kelp or barilla, which was finally converted into ashes. After I had burned sufficient of it, I allowed the fires to go out, and gathered the ashes carefully, to which I added a quantity of fresh water and stirred it about carefully, preserving the fluid in open iron pans, which I placed upon fires and evaporated, and had carbonate of soda as the result; and, although on a desert island where there is supposed to be nothing, my book informed me that kelp or barilla was the best article from which to make carbonate of soda, and some kinds of sea-sand the very best base of which to form glass. Having thus procured the component parts of which to make my glass, I set to to make a large clay pot in which to fuse it, that would fit in the base of my iron-smelting furnace, so as to be surrounded by the air blasts. My clay pits fitted me out with this without any trouble, and I then had to manufacture a level plate of iron, about two feet square, with a raised rim of some inch and a half in height, and this I placed in a horizontal position in front of the door of the furnace, and rigged above it a large iron roller to work by machinery, that could be passed over its face. I then mixed my ingredients by hand in the following proportions:—
| Prepared sand | 400 lbs. | |
| Carbonate of soda | 250 " | |
| Ground chalk | 30 " |
and put the empty clay pot into the furnace and started an immense fire around it. As soon as it was at a white heat I filled it with my mixture, placing it in the pot by means of a long iron spoon some six feet in length, protecting my face with a mask of goatskin, and my hands by gloves of the same material. When vitrification was complete, which took place in about eighteen hours, and which I ascertained by plunging a long rod of iron into the pot, I ladled out a lot of the mass by means of a clay-lined, long-handled, iron ladle, and poured the rapidly-cooling but pliable substance upon the iron table constructed for it, and, pressing the iron roller upon it in all its parts, soon rolled out a sheet of glass two feet square and at least an inch and a half thick. Allowing this to cool, I repeated the process after removing it, till I had made six large squares. I then changed the roller so as to come lower down to the iron plate, and by this method commenced turning out sheets of plate glass two feet square and about one quarter of an inch thick. My task was done. I had all the glass I should ever want as long as I should live; enough for the side lights of my boat, and also for windows to the Hermitage. Fully satisfied with my task, I allowed my fire to go down, and the large slabs of glass to cool.
On the next day I set to work to polish the glass I had made, and this I found a laborious and slow task. But it had to be done, and I commenced with fine pulverized and sifted sand, or rather quartz, and ended with chalk. It was many weeks before all was done, for I needed emery to help me in this task, and could find none, and had to make other things do. But at last I had four fine slabs of plate glass quite well polished and clear, each two feet square, and one and a half inches thick; and several that were of a quarter of an inch in thickness, many of which I had broken in attempting to polish them. The latter were soon fitted into position as window lights in the Hermitage, and pleasant enough they made the interior look. The former were made to fit into four holes cut out of the solid iron of the boat and fitted with flanges, into which they were set with great care by means of what the Chinese call chenam, a sort of water cement made of lime, oil, white of eggs, and clam shells powdered fine, used by them in making all their vessels water-tight. These four panes of plate glass, each two feet square, and an inch and a half thick, were placed at either end and both sides of my boat on the slanting roof, and gave me a chance to see in what direction the boat was moving, to avoid obstacles, and aid me in submarine navigation. They were also thick enough to withstand a blow of great force, and not to be affected by the pressure of water upon them when at great depths; but, to preserve them more fully from any danger, I built outside of them all a wire screen, the meshes of which were perhaps two inches apart, and distant from the face of the glass outwards some six inches, made of strong iron wire at least three eighths of an inch in diameter, so that if by chance the boat should receive a blow, or be forced upon or back against any object, these screens would receive the blow and not the naked glass, although I am ready to believe that the latter would have sustained an immense shock without breaking, it was so thick and perfect, without crack or flaw. I should have said that all my glass had just the faintest tinge of green, caused by the minute particles of iron in the sea-sand of which it was composed, of which I had not been able to completely free it, although I had used magnets to extract large portions of it; but enough remained to give it this very light tinge of which I have spoken.
I had no difficulty in cutting my thin glass into any shape I desired, by means of case-hardened steel, which would scratch it deep enough to be broken off, although a glazier's diamond would have perhaps performed the operation better; but a piece of sharp-edged chilled-steel answered all practical purposes. Later on I had occasion to again make glass, but at this time I did not waste a moment in making household utensils, glasses, or bottles, my earthenware, wooden ware, and ironware doing excellent service for me, and I had need of no utensil that they could not supply.
With my submarine boat perfected and supplied as it now was with its immense windows, I made many trips, and the sights under the water that my eyes gazed upon I could write thousands of pages about. I made no great discovery, however, in all my wanderings, except to find two more oyster-banks, more to the northeast than the first one, but not so prolific. I saw often many creatures that never come to the surface, and for which there is no name, some of them small and seemingly harmless, and others quite frightful and startling. I passed over, upon three different occasions, enormous cuttle-fishes, or squids, with tentacles at least six or eight feet in length, and eyes three inches in diameter; but they never, upon any occasion, paid the slightest attention to my boat, but remained perfectly motionless, clinging to the stony bottom, waiting for their prey, and I took good care never to disturb them. Immense crabs and lobsters, the very patriarchs of the ocean, often lay on the bottom to my view, and seemingly deformed and curious fishes, large and small, some like serpents and some like inflated balls, often met my view as I floated along with the tide a few feet above the bottom. I never wholly got over the sensation of being at the bottom of the ocean; it always seemed as if I had entered another world, where all was changed, and in which every living thing was compelled to keep an eternal silence.
Many parts of the bottom, especially that near the pearl-oyster reef and the approaches to Stillwater Cove, became, shortly after using my glass windows, as familiar to me as similar places would have been on land; there being fully as many distinguishing marks, peculiar in themselves, as upon the rocks and protuberances of the island itself. I loved this lonely under-water drifting about, and indulged in it as a recreation as well as to increase my store of pearls. I sometimes watched for hours the habits and movements of the animals below me, that seemed not to care for my presence; but quite often some huge monster of the sea would pass by me, making me hold my breath with awe, if not fright. But I often thought that my iron boat would be a hard mouthful for anything beneath the waters to attempt to swallow.
I had long, long ago given over any idea of being attacked by savages, and my nerves had become again, as in my younger days, hard as steel; yet I often used to think of how I could lie concealed in this boat, beyond discovery from any source, should I ever be attacked, or how, rising to the surface amongst a fleet of canoes, I could spread dismay by my appearance alone from the bottom of the ocean, among any body of savages, however numerically strong or valiant.