Three years later, when he was now nineteen, he gave still further proofs of his ingenuity:—
“In January, 1815, my father gave a lecture on electricity to the Birmingham Philosophical Society, of which he was a Fellow, I performing the experiments. At that period the means of securing electrical action were either imperfect, or, at best, not very generally known. A previous attempt (by another Fellow of the Society) to give an illustrated lecture on the subject had utterly failed; and it was confidently believed by various members that, in the theatre of the institution at least—whether because of the crowded audiences usually attending the lectures, whether from insufficient ventilation, or from some unknown cause—all further attempt was useless. This stimulated my father to the effort, the more so as his successful lectures, previously mentioned, had been given under circumstances far more unfavourable. His credit was thus staked upon the issue, and he resolved, and I with him, that no effort should be spared to secure success. We carefully examined the whole of the Society’s apparatus, and brought it into complete order. Remembering an exhibition of constellations at one of my father’s former lectures, I went to work to prepare more, which I desired to make on a much larger scale; but glass, the material on which the tinfoil was laid, being not only inconveniently fragile, but at that time, on account of the high duty, an expensive article, I tried the substitution of cardboard, which fortunately I found to be, when quite dry, a satisfactory non-conductor. Using this, I produced several constellations of such size as to be well seen by a large body of spectators; and, which delighted me even more, I so arranged one, viz, that of the Great Bear, that while receiving the spark it was kept in constant revolution. At length we got everything to do well; but our elation at this preliminary success was considerably checked by hearing that our predecessor had thus far done as well as ourselves. This made us very anxious, and our care was redoubled. Observing that the lecture-table was covered with lead, surmounted with green baize, and fearing that this combination would in some measure rob our conductor (the nap acting as so many points), we covered the whole with glazed brown paper; and again, anxious lest any accumulation of electric influence, either in the subjacent lead or elsewhere, might be troublesome, we crossed the table with a number of wires, which, being first brought into connection below, were passed through the floor, and lastly, being thrust into the spout of a pump in the basement, were brought into contact with the column of water within, so as to make our conduction, or rather abduction, complete. We also took advantage of a furnace, which had been set up behind the lecture-table for chemical purposes, to diffuse as much warmth as possible over our whole apparatus, that all dampness might be kept away.
“At length the important night arrived, and, notwithstanding all our precautions, we went to the lecture-room in great trepidation. The clock struck seven, and the electrical machine, which had been kept near a large fire in the apparatus-room till the last moment, was carried in and attached to the table. The lecture began, and the machine was set in motion, while we stood in breathless anxiety to watch the result. To our inexpressible relief we soon saw that it was in full power; and experiment succeeded experiment without the slightest failure. All had proceeded well till about the middle of the lecture, when suddenly the rod of the winch, which, with superfluous caution, had been made of glass, snapped in two, and the machine was brought to a stand. Though enough had been done to establish the success of our attempt, my father, naturally anxious to complete his lecture, and remembering that he was in the midst of a manufacturing town, inquired earnestly whether any one present could furnish a substitute of any description, however rude. One or two gentlemen immediately disappeared, and, meantime, my own machine, which had been brought as a provision against mishap, was used for some minor experiments, for which its power well sufficed. While this was going on my brother Edwin had carried the broken winch into a small workshop on the premises, and, sawing off the leg of a stool, had shaped this at the ends, fitted it to the winch handle, and, returning to the room, attached it to the socket on the axle of the machine, which again began to revolve, so that when our kind friends returned with their substitutes the necessity for them had passed away, and the lecture went on swimmingly to the end; my Great Bear, which was, so far as I know, a novelty, attracting particular attention, and eliciting, contrary to the rule and usage of the society, a round of applause.
“One of the loudest foreboders of evil consoled himself for his error by remarking on the number of assistants ‘Hill’ had had, adding that he had better have brought his wife and all his family to help him. So trifling a circumstance would not have been noticed here had it not touched the key-note of our success. In our course through life, from the beginning to the present hour, each one of us has been always ready to help the others to the best of his power; and no one has failed to call for such assistance again and again. Each one, I am sure, recognises in this fact a main cause of such success as he has attained; and I cannot too emphatically declare that to mine it has been essential.
“In the following January my father gave a second and last lecture on the same subject. Emboldened by our past success, we proceeded to experiments involving greater risk of failure; among others a thunder-cloud, which, to effect its discharge (whereby a model building was to be blown up with gunpowder), had to be moved by electric influence through a distance of not less, I think, than eight or ten feet. But the crowning illustration, with which the lecture concluded, was a revolving planisphere of my construction, four feet in diameter, and representing all stars, of not less than the fourth magnitude, within forty degrees of the South Pole. Wishing that the various magnitudes should appear in the illustration, I devised an arrangement for that purpose. For producing the sparks to represent stars of the first magnitude, I cut the approaching edges of the tinfoil into a round shape, and placed them about one-twelfth of an inch asunder; for those of the second magnitude I gave the edges a pointed shape, also reducing the space between them to a minimum; for stars of the third and fourth magnitudes, while retaining the same arrangement, I produced further obscuration by covering the one with a single thickness, and the other with two thicknesses, of thin paper. To represent the Magellanic clouds was a more difficult matter; but here also I hit upon an expedient. Piercing the disc, in the proper places, with holes proportionate to the size and in the form of the respective nebulae, I placed behind each hole in a plane parallel to that of the disc, and distant about half an inch from it, a piece of paper somewhat more than sufficiently large to correspond with the perforation; and I so arranged that this paper was illuminated by sparks at the back of the disc. When I add that the planisphere thus illuminated was at the same time kept in constant and equable revolution, I shall perhaps be regarded as justified in the belief entertained at the time that the whole result was a more exact representation of the starry heavens than had ever before been produced. The applause previously given to my Great Bear was more than redoubled on sight of my Southern Sky, and the lecture terminated amidst the congratulations of friends, my father being, of course, greatly pleased, myself sufficiently elated, and the whole family triumphant. I may add that a full description of my planisphere will be found in the ‘Philosophical Magazine’ for October, 1818.”[36]
In 1816 he devised and constructed an alarum water-clock:—
“As a complete description of this might weary the reader, I will give only a general conception of its structure. As already implied, the lapse of time was to be marked by the flow of water, and the most obvious difficulty being to render this equable, I employed for the purpose a floating syphon. The tube, which was so fine as to pass only about three drops per minute, was stuck through a flat piece of cork, which floated on the surface of water in a tin can; and as the water issued from the syphon it dropped into another can, though of much smaller size, hung at one end of a balance; so that, as this latter can filled, it became heavy enough to bear its own end of the beam down, while the opposite end, being of course tilted up, struck the trigger, which, as in ordinary alarums, released the weight, thus setting the clapper in motion. Now the length of time required to give the counterbalancing weight of water depended, of course, on the amount of weight put on the trigger-beam; and this was varied according to requirement, principally by means of a sliding weight, hanging from the beam as from a common steelyard. This sufficed so far as quarter hours were concerned, additional means of some complexity being used for securing the observance of smaller portions of time. The end was that I could count on being called within three or four minutes of the time fixed upon. In its early days, however, I was sometimes annoyed by irregularity, and, upon careful inspection, I perceived that this was caused by dust, which, falling into the water, found its way into the syphon, and impeded the flow. To remove this inconvenience, I enclosed my alarum in a box, taking care also to change the water with sufficient frequency. I remember that on the evening when I first got the machine to work, not willing to leave my new light under a bushel, I fetched up half-a-dozen boys into the room where it stood, that they might see and admire. When I had explained the mechanism, and arranged for a réveille at the end of a quarter of an hour, the boys sat down in expectation; and probably being over-worked, according to our practice at the time, one of them fell fast asleep. Great was my delight, and great the amusement of his companions, when, at the end of the time, this, the first person ever awakened by alarum of mine, started up with a sudden exclamation of surprise and alarm, showing that my little machine had effectually performed its duty.
“I may here remark that for one machine that I executed there were many that I devised. Thus I find the following entry in my Journal about a year later:—
“‘December 21st, 1817.—I also wish to make a model of a boat to be driven by pumping [in] water at the prow and forcing it out at the stern. This is an idea of my father’s; and I think it will obviate the objection against driving canal boats by machinery, which is that the paddles agitate the water to such a degree as to injure the sides of the canal’
“A few years later I set down another first conception, this time of my own, which, however, I never carried further. The record is as follows:—