February 24, 1893. J 



SCIENCE. 



lOI 



has been pursued up to the present, viz., the visiting of engineer- 

 ing works, in which you were accompanied by Mr. Lincham, who 

 has explained that which you were witnessing, a point of very 

 great advantage to yourselves. I may say here that I think you 

 are very highly indebted to the head of Section A for his valuable 

 suggestion in starting the society. That during the season you 

 have visited such places as the Arsenal, the Hydraulic Power 

 Company at Wapping, the Tower Bridge, Messrs. Simpsons' 

 Loam Moulding, Messrs Penn, Maudslay, the Deptford and City 

 Electric Lighting Stations, and one steamboat, the " Dunnotar 

 Castle." 



Henceforth you are not only to continue this branch of your 

 study, but jou propose to prepare papers for reading and dis- 

 cussion, and to obtain the friendly services of persons competent 

 to lecture upon engineering and cognate subjects. Now I find 

 great difBoulty in addressing you. I need not enlarge upon the 

 importance of engineering; your presence shows you appreciate 

 that. I hardly like to give you history, although within my own 

 active work since my apprenticeship there has been so great a 

 change, in mechanical engineering especially, as to afford me 

 means for an ample chronicle. 



Perhaps I may be pardoned for alluding to my early work-shop 

 days. There were then no railways to and from the city; the 

 Greenwich Railway was only under consideration. Most engines 

 used steam of no more than 3 pounds pi'essure. There was no 

 planing machine, no slide lathe. If an engine-crank had to be 

 turned, the pin was tooled first, and then the shaft afterwards, 

 by means of a hanging tool, and the throw was much what it 

 pleased Providence to make it, so that in a double-cylinder engine 

 it frequently happened that the two throws were not exactly the 

 same. Boilers were fed by a feed-head, and if the pressure be- 

 came greater than three pounds, the water was ejected, and thus 

 became a sort of safety-valve. 



The notions regarding steam pressure were very vague. I 

 have a great regard for a very interesting old book, " Belidor's 

 Architecture Hydraulique," in which I read of a boiler, erected in 

 France, having a heavy superstructure to keep down the pressure, 

 and much the same construction was used in the boiler at York 

 Rd., Charing Cross, which supplied London with water. Sir 

 William Siemens used to say that this load of masonry was clearly 

 for the purpose of providing a large number of missiles in case of 

 an explosion. When quite a child I was taken by my nurse to 

 see the water-wheels at London Bridge, which were also used 

 for the water-supply, and even at that early date engineering had 

 a great fascination for me. Everything then was different. The 

 opportunities for technical learning, other than those from ap- 

 prenticeship, were simply nil ; that is now quite changed. This 

 institute is suSicient to show it. You may learn and learn well, 

 and it would be to your eternal shame if you did not ; but 1 want 

 you, in the pride of your strength, not to deal hardly with the 

 older hands, but to remember that, though they bad not the ad- 

 vantages, they made the progress, and must have had very much 

 in them to do this when we consider their resources. One great 

 advantage of instruction in principles is this — aspiring inventors 

 need not attempt impossibilities. Suppose a man were to say, •'! 

 have a machine that will produce marvellous results if you will 

 concede far its purposes that two and two make five, as I say 

 they do." His friends would probably call in a doctor or conduct 

 him to a lunatic asylum. But this method of stating the case 

 is not so very absurd. Much labor has been spent on inventions, 

 which were impossible, but where, from want of instruction, the 

 impossibility did not make itself apparent — where the two and 

 two could not easily be seen, which it was endeavored to make 

 into five. The learning of the principles of mechanics will show 

 that you cannot get more work out of a machine than you put 

 into it, and will thus put a stop to useless inventions. Let us 

 consider the connection of the past with the present by the great 

 examples of progress. Boiler pressure has increased from three 

 pounds to 150 pounds, and these pressures have been utilized by 

 engines of continually increased expansion with single, compound, 

 and triple cylinders. The triumphant position of the steam-jacket, 

 though many times questioned, is worth noting. First used by 

 Watt, he does not appear to have been aware of the principle 



involved. Forced draught, by which I mean a closed stoke- hold 

 (not the closed ash-pit, which is very old); very curiously this 

 adjunct to marine propulsion was seen by me at work in the 

 United States as long ago as 1853. I spoke of it on my return, 

 but no attention was paid to it until the principle found appli- 

 cation in torpedo boats. I will read from my note-book for 

 1853: — 



"Oct 11, 1853. Camden and Amboy railway steamer 'Rich- 

 ard Stockton.' Tonnage 651. Two boilers on each after spon- 

 son, machinery made in 1853 by Haslem (?) and Hollingsworth, 

 Wilmington, Delaware. Wheels 23 feet in diameter, 9 feet wide. 

 Boiler -f^ of an inch thick, proved to 55 pounds, to work at 39. 

 Actual pressure 25 pounds. Boilers have two fire-places in each; 

 they burn anthracite coal ; each one has a powerful donkey work- 

 ing a blower, which is on deck, and which blows into the boiler- 

 room, the door being kept sbut, and the stoker underpressure." 

 The object of the arrangement was to prevent a tongue of flame 

 coming from the fire in case the door should be left unlatched. 



Large steamers were constructed on most unsatisfactory prin- 

 ciples in the early days. Nothing could have been more unlike a 

 box girder or braced structure than the wooden built ships, but 

 the present double bottoms and iron decks form probably as good 

 specioiens of girders as can be made, competent to carry , without 

 straining, their own weight and that of their cargoes, while the 

 points of support are changed at every movement by the force of 

 the waves. I may mention also the great advances in the speed 

 of ocean steamers, and wish I had time to describe carefully to 

 you how much we owe to the late Mr. William Froude, who, by 

 means of bis admirable paraffin models, showed how to predict 

 with absolute accuracy the performance of the full-sized vessel. 

 The material employed was very easily worked, and could be re- 

 melted for further models. 



Another great feature in the engineering of to-day is that of 

 making subterranean communications by means of tunnelling 

 with the aid of shields and compressed air. The Thames tunnel 

 was the earliest of these great works, and the shield was in sev- 

 eral sections, so that each could be advanced separately by a 

 screw-jack, but there was no compressed air and the difiSculties 

 were very great, for in some places an artificial soil had to be 

 constructed by tipping in clay. I was shown these works when in 

 progress by the eldest Brunei. Compressed air was introduced 

 by Sir Thomas Cochrane (afterwards Earl Dundonald), who took 

 out a patent in 1830 (No. 6018). I knew him very well ; he was a 

 clever engineer, but, not being trained, he sometimes made mis- 

 takes in detail. His patent was for " Excavating, sinking, and 

 mining," and included "an apparatus for compressing atmos- 

 pheric air into subterranean excavations, so that its elasticity 

 may counteract the tendency of superincumbent water or moist 

 earth to fill such excavations," and he refers to " the undertaking 

 which is now executing beneath the river Thames at Rotherhithe." 



Now let me say a few words about electricity and its present 

 condition. Faraday was the great author, and to him we owe 

 the science of electrical engineering, although his discoveries 

 have been considerably developed by many other great workers, 

 whose names are legion, one of the greatest of these being my 

 late valued friend. Sir William Siemens, who. though he died 

 some eight years ago, I cannot now mention without bitter re- 

 gret. You have often been told that a little learning is a danger- 

 ous thing. This is a great mistake. Learn all you can; it is only 

 a shallow knowledge of everything as your end and aim that is 

 wrong. Sir William Siemens used to say, "Learn one thing 

 thoroughly, and after that a little of everything." The develop- 

 ment of practical electricity began with the telegraph, and I re- 

 member bow astonished we all were when a murderer was cap- 

 tured by its aid ; but telegraphy is fast giving way to telephony. 

 Electric arc-lighting was first shown at the Exhibition of 1862, 

 applied to light-houses. Since then it has been much further 

 developed, but the incandescent system of Edison and Swan is, 

 after all, the most useful extension of electric lighting. I do not 

 want to introduce political economy, but when the advance or 

 hindrance of engineering is due to parliamentary interference, 

 the science deserves your study. Several years ago, when the 

 time was ripe for general electric lighting, Mr. Joseph Chamber- 



