222 



THE CIVIL ENGINEER AND ARCHITECTS JOURNAL. 



[July, 



Among the remaining models, we observed Messrs. Blake and Varley's at- 

 mospheric pile-driving machine, — Mr. Varley's rotating air-pump, — Mr. S. P. 

 Bidder's simple and effective coal-drops, — Mr. Dodd's rail-straightening 

 machine, — Mr. Southam's wedge and screw fix, — Mr. Thornton's improved 

 hydraulic lifting-jaclt, — Mr. Wetherall's iron-twister, — Mr. Chrime's patent 

 fire-plug valve, — Mr. Beattie's new wooden railway, with the drawing of the 

 system of manufacturing it, — a model of a folding boat, of which each side 

 was made of two thicknesses of water-proof cloth, filled in on Capt. Light's 

 principle with very buoyant reeds, rendered non-absorbent, and consequently 

 rendering the boat incapable of sinking, even when full of water, and even 

 when partially torn by accident. The expedition in search of Sir John 

 Franklin has heen furnished with boats of this description, in order that 

 they may be easily transported across the ice, and may bear injuries which 

 would destroy a wooden boat. The Gutta-Percha Company sent a selection 

 of their products from the rough material throughout all its stages of manu- 

 facture to the finished articles. Mr. Chubb's safety chest and locks and 

 keys, — Mr. De la Ton's ingenious locks and bolts,— Mr. Defrie's improved 

 dry gas-meter, — the new Aneroid barometers, — and numerous other inte- 

 resting models and specimens. 



June 20. — JosHtr.\ Field, Esq., President, in the Chair. 



" On Harbours of Refuse." By the Right Hon. the Earl of Lovelace. 



The paper consisted chiefly in a succinct review of the Reports of the 

 Commissioners on Shipwrecks and on Harbours of Refuge; giving the 

 opinions of the naval oflicers and civil engineers on the necessity for har- 

 bours, in certain situations, and the uaval qualities possessed by those 

 positions — the possibility of constructing harbours in them, and the nature 

 of the structures. The necessity for harbours on our coasts, capable of 

 sheltering fleets from storms in peace, and the enemy during war, appeared 

 to be admitted, particularly at the present moment, when the disturbed 

 state of the continent and the restless character of our near neighbours 

 were considered. It was stated, that, of various situations pointed out, 

 that of Dover was the only one yet decided upon, although great works 

 are contemplated at Portland, where, from Mr. Rendel's designs, a system 

 of construction would be adopted, which would be both economical and 

 stable, and, at the same time, would afford employment to a class of persons 

 whose labour it had been diflicult hitherto to use efficiently. The various 

 projects of floating breakwaters, and other artificial shelter for vessels, were 

 then examined, and were generally condemned, as entirely inefficient for the 

 objects proposed. 



The questions relative to the movement of sand, the drifting of the 

 shingle, and the deposit of silt in Dover Bay, and other places, were treated 

 at great length, and reasons given for the various forms of construction, and 

 of the projects for meeting the difficulties induced by these circumstances. 



The nest question was the place of the harbour, and the mode of con- 

 struction of the works. After quoting all the authorities on both sides, 

 including the naval officers, the commissioners, the civil engineers, and the 

 scientific writers, the preference was given to a large harbour, with two 

 entrances, so placed as to allow a sufiicient ruu of the tide through it, to 

 prevent any very considerable deposit of silt, but so constructed as to afford 

 shelter to the vessels within. The pier walls inclosing the harbour to be 

 built vertically up from the bottom, or with a very slight inclination in their 

 height, instead of throwing in masses of rubble stone, to find its own angle 

 of repose, which, it was shown, was not less than four or five to one, and 

 that it only attained solidity after a lapse of many years, even with a due ad- 

 mixture of small materials to fill up the interstices, and after constant sup- 

 plies of stone, to replace that which the seas had removed. The reports of 

 Capt. Washington were quoted, to prove the failures that had occurred at 

 certain harbours in Ireland, where it was stated that the long slopes had 

 been destroyed by the sea, and had ruined the harbours they were intended 

 to protect. The proceedings at Cherbourg and Plymoutli were followed in 

 great detail, with a view to deducing arguments against the long slopes, and 

 in favour of vertical sea-walls. 



The protest, by Sir Howard Douglas, in favour of long slopes, was 

 examined at great length, and the arguments used on both sides were 

 analysed with skill and candour. 



Colonel Emy's theory of the effects of the " Jloat dii fond," was care- 

 fully examined ; and, without going to the entire length that he did, it was 

 admitted, in many cases, the effects produced were as he described them, 

 and that the subject, as he had brought it forward, was well worthy the 

 attention of civil engineers. 



The placing a vertical wall upon a substratum of rubble, in the form of a 

 long slope, was shown to be pregnant with mischief, and had never heen 

 successful ; and that the adoption of that system at Cherbourg had been a 

 matter of necessity rather than of choice. 



Mr. Alan Stevenson's clever experiments, on the force of waves striking 

 opposing bodies, were given ; and it was urged, that the force shown to be 

 developed by a breaking wave could not act upon a vertical wall, up and 

 down which it would merely oscillate ; whereas it might fall, with all its 

 aocumidated force upon a slope, upon which it would naturally break. In 

 conclusion, it was urged that, although for Dover, which was the spot 

 whereon to mount guard over the channel, in order not only to prevent 

 invasion, but to maintain our present naval supremacy, it might be permitted 

 to expend a large sum of money ; yet it would not do lo have several Hovers ; 

 and, therefore, it behoved the authorities to consider carefully the site, the 



plan, and the method of construction, before commencing works, in which, 

 in the present state of engineering science, the experience of the past 

 should be used to avoid the errors that had occurred in former and similar 

 works. 



In the discussion which ensued, and in which the principal civil engineers 

 engaged on great hydraulic works took part, after justly complimenting the 

 Earl of Lovelace, for the very able and impartial analysis he had made of 

 the evidence contained in the Government reports, and the documents in 

 his possession, the speakers explained most satisfactorily the actual circum- 

 stances and conditions of the works which had been instanced as failures ; 

 and it was shown, that far from being expensive or useless works, they had 

 been completed within the original estimates ; and that wherever the con- 

 struction had required restoration, or addition, it had arisen from the use of 

 defective materials, whicli, being on the spot, it had been obligatory to em- 

 ploy, and not from the use of the long slope, which, as compared to vertical 

 walls in similar situations, was shown to be more durable, and to have been, 

 in many instances, successfully substituted for vertical walls, after they had 

 succumbed to the assaults of the raging billows. 



INSTITUTION OF MECHANICAL ENGINEERS. 



June 13.— J. E. M'CoNNELL, V.P., in the Chair. 



ON THE BALANCING OF WHEELS. 



Mr. M'CoNNELL read the following interesting paper on the above 

 subject: — The paper treated ou the balancing of wheels as a very im- 

 portant matter, as most of the accidents from carriages jumping off the 

 line, had arisen from the balance in the wheels of the engine. 'The first 

 who made this matter of practical observation was Mr. George Heaton, of 

 Birmingham, on examining a lathe in the turning-rooms of Earl Craven, 

 the pulley of which he found to be out of balance. This he remedied, and 

 the lathe worked well again. Mr. M'Connell instanced several railway 

 accidents of late, which had arisen from a want of proper balance in the 

 wheels of the engine. He then proceeded to illustrate the usual method 

 of balancing the wheels of locomotive engines, which he considered an 

 improper one, and, on reference to experiments with another model, pointed 

 out the desirability of obtaining an accurate balance in the piston and 

 piston-rod. 



In the course of the paper, Mr. M'Connell exhibited various experi- 

 ments with a model railway carriage, explanatory and illustrative of the 

 statements advanced in the above paper. The first experiment was 

 made with wheels in balance, the motion to which was given by a spring, 

 and the sustained regularity of the motion was unexceptionable. In the 

 second expei'iment, a small piece of iron was inserted in the wheels, and 

 the balance consequently destroyed — the natural tendency being to cause 

 a Jumping and jerking motion, to obviate which was the object sought in 

 this contrivance. Similar experiments were made, to show the necessity 

 of adopting a similar system of balancing the piston and piston-rods, in 

 order to obviate this same jumping motion. 



In explanation, Mr. M'Connell said, that the wheels could he properly 

 balanced together. First, one wheel was balanced, and then they put the 

 other wheel on upon the other side of the engine, and balanced it in the 

 same manner. When the matter was first placed before Mr. Robert 

 Stephenson, that gentleman considered it of no service, and it met with 

 much opposition ; but since that time Mr. Stephenson, and many other 

 gentlemen, had adopted a plan of balancing their wheels, which, in his 

 (Mr. M'Connell's) opinion, was not the correct one. When a locomotive- 

 engine was connected, and the driving-wheels and working part attached, 

 it was lifted up upon centres, and set slowly in motion, balance-weights 

 being added until it moved at a certain speed without oscillating, and it 

 became perfectly settled ou its centres. That plan might answer tolerably 

 well, bat it was the really true mode of balancing wheels. He con- 

 sidered that great evil resulted from the piston and piston-rod not being in 

 balance ; it had been the cause of accidents in several cases where the 

 engine did not leave the rails when the wheels were in balance. If the 

 engine attained a certain velocity — the piston-rod moving 1,001) feet a 

 minute — this momentum became so great, that the engine must jump ; and 

 the front wheels were, in some instances, clear of the road, and they could 

 see between the wheel and the rail. They had an engine at WoJvertoD, 

 fitted up with those correcting weights, and it had been tried, for the first 

 time, that morning ou blocks. The engine at a certain speed on the 

 blocks, threw itself down, and they were not able to run it so fast as 

 raiglit be wished ; but, on attaching tlie balance-weight, the motion of the 

 engine was completely neutralised. 



Mr. MiDDLETON said, that this appeared to be the system of balancing 

 wheels, which had been iulroduced lo the notice of the North-Westera 

 Railway, some years ago, by Mr. Cleorge Heaton, and against which 

 hitherto there had been much prejudice. He felt coavinced that it was 

 one of the best methods ever suggested for securing the safety of the 

 public, when travelling on railways, and a great many accidents might be 

 obviated by the adoption of this, or some similar plan of balancing the 

 wheels of eugiues and carriages. It was supposed that the North-Western 

 line had disapproved of Mr. Heaton's plan, but he was happy to find 

 that there was now some probability of Mr. Heaton reaping the reward 

 of his industry by the use of his patent. 



Mr. CowPER said, that a system of balancing wheels was used by the 



