The exhibition of 1851

About this period everyone was interested in the forthcoming International Exhibition of 1851. I had applied for space to exhibit the process of separating molasses from crystallized sugar by my combined steam and centrifugal apparatus; this formed a very attractive display. The crystallised sugar, with its adhesive coating of brown treacle, was spun round in the wire cage at a speed of 1,800 revolutions per minute; and on throwing a bowlful of cold water into the machine, in thirty seconds the dark sticky mass was like a snowdrift, with its sparkling crystals compactly spread round the revolving basket. Crowds of people would stand round the machine, and seemed never tired of witnessing its operations.

I took a deep interest in the development of the International Exhibition, and as an exhibitor I used to pass long mornings in the building very frequently, prior to its public opening in May, 1851. On one of these occasions I chanced to meet my esteemed old friend, the late Mr. Bryan Donkin, F.R.S., and he went with me to see how my exhibits were being fixed up. Seeing my centrifugal machine, he said: "Why do you not show that old scheme of yours for raising large volumes of water by centrifugal force? " "Oh," I replied," I had almost forgotten it." He said, "Everybody is fond of looking at a cascade, and a large body of water such as you can lift would make one of the most interesting exhibits in the mechanical department." Thus encouraged, I next day sat down to my drawing-board, and schemed a combined- engine and centrifugal pump, which I afterwards exhibited. There was very little time to make all new patterns and large loam castings; indeed, it seemed almost impossible to do so. But I posted my drawings to Messrs. George Forester and Co., Engineers, of Liverpool, who had previously executed some important orders for machinery for me. My instructions were: "If you can make the combined steam engine and centrifugal pump in thirty-two days from the receipt of this, and undertake to deliver it at the Exhibition building on the thirty-third day, set to work at once and make it; but if you cannot undertake to do so, do not touch it at all, as I must hold you responsible. I know it is a most arduous task, but if you execute so important an order in so short a period it will do you much credit, and I will put on the side of the machine a conspicuous brass plate, giving the full address of your firm as makers, with the date of order and date of delivery engraved thereon." The result was that the whole apparatus was admirably finished and delivered one day before the prescribed limit. Some months later Messrs. Forester and Co. executed for me two combined engines and pumps, each of which, when set temporarily at work in Toxteth Park, Liverpool, was found to discharge 109 tons of water per minute at a height of 7 ft. above the source of supply. These pumps were afterwards erected for the drainage of some sugar estates in Demerara, which lay 5 ft. below high-water mark in the tidal river into which they were drained, and each of them lifted a small rivulet 10 ft. wide by 18 in. deep, flowing at a speed of three miles an hour.

To my no small surprise, I found that I did not stand alone in the Exhibition as the inventor of centrifugal pumps, for there were two others, one by Mr. Appold, and another by Messrs. Gwynne, from the United States; each of these was doubtless a separate and distinct invention.

Notwithstanding my frequent visits to the Exhibition to superintend the erection of my exhibits, the place remained as fresh and as full of interest as though I had never been inside those magic walls of glass. How vividly still my mind retains the impression of the opening day; what a glorious May morning, the crowning day of expectation to so many thousands! We were warned that unless we started from home very early, we should never reach the building by 11 a.m. I lived then on the road to Highgate, only two miles off. My wife and my eldest sister left home with me in a brougham at 8 a.m. Even at that early hour the streets were thronged; all London was astir, and as we slowly neared the Park the streets were densely crowded; everyone in holiday attire, all looking joyous and brimming over with eager expectations. Very soon our quiet trot had dwindled to a walking pace, and as we entered the Park by the Marble Arch, our progress ceased in an absolute stop, followed by a little move preparatory to another long stop. We had got into the Park by 9 a.m., and there were yet two hours, but we had begun even then to fear we might not reach the building in time. There was no intentional obstruction, and the police did all they could under impossible conditions; we were hemmed in on all sides by carriages and pedestrians, and were almost immovable. An hour's intermittent motion had brought us from the Marble Arch to the Piccadilly entrance, from which rolled another avalanche of almost hopelessly struggling humanity. Yet