THE EXHIBITION OF 1851

The Centrifugal Pump -- The Opening Day -- Consultations with Inventors -- Continuous Brakes for Railways

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 all was good-humour and high expectation; tickets were flourished from innumerable carriage windows, and fair ladies in their sweetest and most persuasive tones, asked aid of the police, who were powerless to help them. Another half-hour from the Piccadilly entrance brought us in full sight of the fairy palace, which sparkled in the sun, but was as yet a few hundred yards distant. But we were in an almost solid mass of carriages, horses, policemen, and pedestrians. A look at my watch showed me that there was no hope for us if we kept our seats in the brougham. We were within fifty yards of the building, and we agreed to get out and chance struggling up to the door on foot. Hundreds of ladies in their satin shoes descended from their carriages to the gravel, and with their beautiful dresess pulled tightly round them, trusted to their feet. In charge of my two ladies I showed my tickets and got, at last, passed on to the doors, which we entered ten minutes before the appointed time, and just three hours after we had started. We hurried to our places, and could now breathe more freely; the air was full of perfume from the sweet flowers that filled all vacant places, and added a lustre to the gorgeous scene. When the formal processions had gone round the building, there came the one great treat of the opening day, never to be forgotten by those who heard it. The sister of my old friend Alfred Novello, Miss Clara Novello, sang the National Anthem, and by a supreme effort, her full melodious voice filled the whole space with a glorious volume of sound that could not fail to inspire the deepest feeling of loyalty. And as her voice rose and fell to the cadences of the beautiful Anthem, the thousands of faces of those present showed at a glance how all were moved by feelings of deep emotion and loyalty to Her Most Gracious Majesty, and to Prince Albert, whose cherished dream of the International Exhibition was thus so happily realised.

Returning again to the quiet daily routine, life at that period found me pretty regular in my attendance at the office in Queen Street Place, where I often spent a few hours with some client, who had sought advice in reference to an invention, possibly more or less crude and impracticable, or, it may be, of great value if only a little more mechanical knowledge had been expended on its details. Such investigations were sometimes very interesting; and I well remember several inventions which were brought before me at that time, and which have since taken their place among the important mechanical improvements of the present century; while many others that were essentially bad and wholly impracticable were fought for by their luckless inventors with a tenacity worthy of a better cause. It was just this class of inventors that one could not convince of the false notions under which they laboured; if a man knew so little of mechanical laws as to suppose that by some tricky arrangement of levers which he had devised he could make the descent of 20 lb. lift up 40 lb. to the same height, it took a vast deal of labour to convince him of his error; and he paid consultation fees with the inward belief still clinging to him that, somehow or other he was right, only he could not make me see things in the proper light. But generally I found it possible to bring home to the most prejudiced minds such unpleasant facts, and I have in many cases received the most frank and friendly acknowledgments from men who would have spent hundreds of pounds in search of the impossible had not an hour's discussion shown the fallacy of their convictions.

During the years 1852 and 1853, I was very busy with inventions of my own, for I find that in those two years I took out no less than twelve patents, that is, on an average, one every two months. These being mechanical inventions relating to manufactures, there arose, in each case, much studying of details, and many original drawings had to be made in addition to the specifications to be written and claims to be settled. Some of these were followed up with results that were highly satisfactory; but it was my misfortune that inventions sprung up in my mind without being sought, and as soon as a new idea presented itself there was no peace for me until the first crude notions were shaped and moulded into a tangible form, and this again criticised and improved upon. Then came experimental research, or in many cases the invention was patented as a mere theoretical deduction because it had to make room for the next: whereas each invention, to be made a commercial success, required to be carefully and forcibly brought under the notice of the particular trade to which it referred.

In regard to one of these patents of 1853 I will just say a word or two, as a mere record of a first proposal to stop a railway train by the simultaneous application of a brake on every carriage wheel of the train. I fully appreciated the advantages of this simultaneous action on every wheel, because by such means a train of twenty or thirty carriages could be stopped just as quickly and as easily as a single carriage, since each vehicle was subjected to the same retarding action; but it was necessary that this should be effected, as far as possible, without any complicated mechanical arrangements likely to get out of order in practice. My invention, which I call the hydrostatic brake, was one of extreme simplicity. Under ordinary circumstances the application of hydraulic power means packed pistons, water-tight stuffing-boxes, inlet and outlet valves, etc., all of which mechanical appliances were, in my plan, entirely dispensed with, and a rectangular cell of vulcanite rubber was used for transmission of the pressure.

The arrangement was as follows:-- A rectangular iron box was held by bolts passing through flanges at each end, by means of which it was secured to the underside of the carriage frame. The interior of the box was 7 1/2 in. long by 4 in. broad and 8 in. deep, and there was fitted inside it a block of wood, not unlike one of the blocks used in street paving, and having a curved lower surface fitting the tyre of the carriage wheel. This block projected downwards from the mouth of the box, and left a space of 1 1/2 in. between it and the upper closed side. Into this space was fitted a hollow rectangular chamber or box of vulcanised rubber, capable of expanding and contracting; it was attached to the wood-block on its lower surface and to the box on its upper side. There was a small pipe which connected the chamber with a continuous pipe leading to the locomotive, where the driver could turn water pressure on or off instantly whenever necessary. Each of the rubber chambers contracted by external atmospheric pressure if connected to the exhaust, and lifted the wood-block from off the wheel; but the instant that pressure was applied, each of the chambers expanded, and pressing on its wood-block forced it in contact with the wheel and retarded the motion. Thus if the wood block were 7 1/2 in. by 4 in., it presented a surface of 30 square inches, and every 10 lb. to the inch pressure on its surface was equal to 300 lb. on the wheel. The main leading pipe was always charged with water, which is non-elastic, and was permanently in communication with each of the chambers. If half a pint of water was exhausted from each chamber, the block was raised more than half an inch from the wheel, and relieved the pressure. Modifications of this simple brake have been made; but it came before its time, and was not accepted by the railway companies. I am pleased to have lived long enough to see continuous brakes universally adopted, for by them vast numbers of persons have been saved from injury or death.