Correspondence relative to the Canal Communi cation in Canada. No. 72.-LETTER from Lieut.-Colonel By to General Mann, SIK, Royal Engineer's Office, Rideau Canal, 4th April 1829. I HAVE the honour to report, for the information of his Lordship the Master General and Right honourable and Honourable Board, that on Friday morning, 3d instant, the dam at the Hog's Back gave way, and in a few minutes about onethird of it was destroyed; fortunately no lives were lost, nor any damage done to the surrounding country. This dam was nearly completed, and the water raised within four feet of the required height, which proves the practicability of the plan, and the correctness of our levels, as the water levels perfectly agreed with those taken by the instrument. The way I account for the accident is this: the contractor having given up the work in November last, it became indispensably necessary to make every exertion to complete the dam before the spring floods commenced, it being the only chance of saving that part of the work which the contractor had performed; I therefore moved up to this work at the Hog's Back, such of the two companies of the Royal Sappers and Miners as could be spared, leaving a sufficient number to furnish guards for the magazines and military chest, and ordered that two officers should constantly be on duty at this work; from that period, Captain Victor, Royal Engineers, who had charge of the work, has scarcely been a day absent, and great praise is due to him and to the other officers, for their unremitting attention during the whole of this severe winter; and I have the satisfaction to state, that every exertion was made to accomplish the desired object of finishing the dam, but the severe frosts formed the earth above water into a solid mass, and when the spring floods came, the pressure of the water separated that which was not frozen from the congealed mass above, and caused a great leakage on the 28th March, which continued to increase, notwithstanding every exertion was made to stop it, until ten o'clock on the 3d of April, when the arch key work, 26 feet thick at the base, gave way about 15 feet above the foundation, and near the centre of the dam, with a noise resembling thunder. I was standing on it with forty men, employed in attempting to stop the leak, when I felt a motion like an earthquake, and instantly ordered the men to run, the stones falling from under my feet as I moved off. The loss of work and materials, tools, &c. I estimate at between three and four thousand pounds. Notwithstanding the present failure of this work, I beg leave to assure his Lordship the Master General and Right honourable and Honourable Board, that I do not entertain the least doubt of being able to establish the dam, but that to prevent a recurrence of a similar event to that which has just taken place, it appears evident that the whole of this work must be carried to its required height in one summer; but as the prevailing sickness renders all operations uncertain, before I commence reconstructing the dam, I propose again exploring the wilderness to the right and left, and taking fresh sections, with the hope of finding some way by which this bold undertaking may be avoided, although from the many examinations I have already given the country, I fear there is but little hope of finding a better route for the Canal at this place, in which case I shall commence re-constructing the dam the moment the spring floods have passed, and you may rely on my using every possible exertion to complete the work before the frost sets in. No. 73.-LETTER from R. W. Hay, Esq. to R. Byham, Esq. SIR, Downing-street, 20 July 1829. I AM directed by Secretary Sir George Murray to transmit to you the copy of a Despatch from Lieut-General Sir James Kempt, inclosing a detailed Report from Lieut.-Colonel By, relative to the failure of the dam at Hog's Back, and also a Report from Lieutenant Pooley of the Royal Engineers, upon the precarious state of the dam at Smith's Falls, and I am to request that you will lay the same before the Master General and Board of Ordnance for their information. Correspondence relative to the Canal Communication in Canada. No. 74. 30 April 1829. No. 76. No. 74.-DESPATCH from Lieut.-General Sir James Kempt to the SIR, Quebec, 30 April 1829. WITH reference to my letter (No. 3.) of the 13th ultimo, upon the accident to the dam at Hog's Back upon the Rideau Canal, I have now the honour to transmit to you a detailed Report (No. 1.) upon that subject, which I have just received from Lieut.-Colonel By of the Royal Engineers, to whom the superintendence of that work is entrusted. It is with great regret that I find it at the same time my duty to transmit a Copy of a Report from Lieutenant Pooley of the Royal Engineers, upon the precarious state of the dam at Smith's Falls. I have directed, Colonel Durnford, the Commanding Royal Engineer in Canada, to proceed without loss of time to the Rideau Canal, with a view to consult with Lieut.-Colonel By upon the most eligible mode of proceeding with that work during the approaching summer; but I have more especially directed his attention to the necessity of ascertaining the most effectual means of averting the recurrence of accidents of so serious a nature in future. You are doubtless aware also that the Welland Canal has given way at the "Deep Cut," and I fear the damage sustained will greatly increase the original estimate for the completion of that work, and create greater difficulty in carrying on the undertaking than was apprehended. I have, &c. (signed) James Kempt. No. 75.-REPORT on the Failure of the Dam at Hog's Back on the Rideau Canal. SIR, Royal Engineer Office, Rideau Canal, I HAVE the honour of acknowledging your letter of the 18th inst. just received, requiring further particulars relative to the failure of the dam at Hog's Back. In answer to which I beg to state, for the information of his Excellency Sir James Kempt, that the failure of the dam is to be accounted for as follows: the Rideau River has been raised about 22 feet by the contractor, when he gave up the work in November last, and it was evident, that unless the water could be rendered passive, by its being raised above the Three Island Rapids, the rapidity of the current would carry all away in the spring, to prevent which I caused every exertion to be made, and the desired object was obtained, for we raised the water 41 or 42 feet perpendicular, and the Three Island Rapids were destroyed; our surface water extending on an uninterrupted level to the Black Rapids, the water, as also the ice, became passive; I constructed three booms at different parts of the river to hold back the said ice until it sunk or was dissolved, and I flattered myself our labours were completed, when unfortunately an extensive leak made its appearance and rapidly increased, No. 70. No. 75. No. 76. Correspondence relative to the Canal Communi cation in Canada. PLAN, No. 4. notwithstanding every exertion was made to stop it. It appears that the earth became one frozen mass from the surface water level of November last to the top of the dam, which is 43 feet above the said level, the dam being upwards of 60 feet high at the time of the accident; 45 feet is the required height, but I added 15 or 17 feet to the height, to give it greater strength, and made the base 200 feet thick. You will perceive by the accompanying Section, that this whole mass of earth about the surface water level was 22 feet in November last, became one frozen mass, resting on the rocks on each side of the river, 180 feet apart; and such was the strength of this frozen mass of earth, that it remained perfect for some time after the torrent had swept all from under it, until the spray, rising with great force, striking the under part, gradually thawed it, and caused it to fall in large flakes, until it became so thin that its own weight broke it. The force of the water was such, that stones of two or three tons weight were tossed about as if they had been blocks of wood, and the frozen earth was carried over the Rideau Falls, a distance of between five and six miles; but as the frozen earth rested on the side rocks, and did not settle with the earth below, which was considerably compressed by the pressure of the water when raised to its height, the water found a passage between the frozen earth and that which was not frozen; but as the puddle behind the arch key work prevented the water from passing through the key work, this passage was not discovered until a sudden rise of the river on the 28th March, when the pressure became more than the unprotected puddle could resist, and it was washed through the arch key work from the height of 15 feet to the bottom; but this did not in the least affect the arch key work, therefore I believed it possible to save the dam, and made every exertion, notwithstanding which the leak increased until about ten o'clock in the morning of the 3d inst. when the water forced its way through the upper part of the puddle at the back of the arch key-work, and began to flow over the top without carrying off any of the coping stones. I then conceived that as the water had found a free passage all was safe; and said to Mr. Sargeant, the barrack-master, who stood on the arch key work near me, "You see "what perseverance will do, the dam is saved." At which moment I felt it tremble, and instantly ordered the men to run. I stood and looked at it for a few seconds, when the stones fell from under my feet as I ran off. It appeared to give way in the centre of the dam, about 17 feet from the base, and in the strongest part. The cause of the failure being thus evident, there is no doubt of its ultimate success; but as the period for working at it is only from July to the end of November, great exertions are requisite, during the whole period, to insure its completion. I therefore propose forming it with timber, filled with rough stone, this season, and leaving the arch key work to be carried up at any future period; feeling convinced that if the work is well conducted during the summer, it must succeed, I therefore hope his Excellency will allow me a detachment of thirty men of the line, to furnish the necessary guards, as the guard duty prevents the non-commissioned officers of the Sappers being of so much use to me as they otherwise would be, and there are no persons I can hire, who are of equal value to them, and much depends upon every part of the dam being well executed. I have, &c. (signed) L' Col. R' Engineers Com3, Rideau Canal. No. 76.-REPORT on the precarious state of the Dam at Smith's Falls. SIR, Royal Engineer Office, Edmund's Rapids, 23d April 1829. I THINK it my duty to report to you, by a messenger express, the dangerous state in which I fear the dam at Smith's Falls is at present. About five o'clock, P. M. of the 20th instant, a leakage was first observed through the arch key work, issuing from it about the top of the lower course, two feet six inches or three feet from the bottom, and extending from west abutment across, to about centre of course, coming through muddy, evidently washing away the puddle. Upon this alarm, a body of about thirty men set to work, excavating behind the key work, in order, by sinking a trench, to discover where the run of water proceeds from, and then to choke and repuddle it; the clay being hard frozen about six or seven feet deep, little progress was made; the working parties were regularly relieved all night, but the thunder thunder storm and heavy rains precluded the possibility of doing much work. By Correspondence three o'clock in the morning the rush of water through the key work had consider- relative to the ably increased since first discovered, and by day-light, when I visited it, the leak Canal Communiextended along the lower course from west abutment, two-thirds across the dam, the cation in Canada. greatest quantity issuing from about the centre, muddy with the puddle; level of water above dam not perceptibly lowered. Mr. Rykert being absent at Brockville, I directed his foreman to persevere sinking behind the key work, over the principal rush of water, and to collect at hand a quantity of fresh puddle, brushwood, sheeting poles, horse dung, &c. to choke it as expeditiously as possible on discovering the run of it; other parties were at work wheeling in clay in front of the dam, opposite the leaks, but with no effect; they continued to work yesterday, and last night. To day Mr. Rykert having returned, I found him pursuing the same plan, but there is so little energy manifested by his workmen or foremen, who do not appear to be com petent to conduct a work of this nature, and so indifferently supplied with tools, that I cannot refrain from expressing my apprehension as to the result. The excavating party had not got down below frost, although about seven feet deep, and had been blasting all the morning. The rush of water had not however much increased, although this evening I thought it was rather gaining ground. Mr. Rykert is of opinion, that the water issues from the fissures of the rock forming west abutments of dam, and from thence follow the line of puddles until it escapes through a key work, or insinuates itself between the artificial work and natural bank, and circumstances seem rather to favour such an opinion; and a considerable stream certainly rushes from the rock or natural bank of river just below this abutment, through the numerous fissures to be seen on surface of the rock in river just above Rykert's store. A small clay dam having been run across the little bight from corner of Rykert's store to dam the water inside, it all escaped through the fissures and left it perfectly dry, but made no perceptible difference in the run of water, either through the rocky bank below the dam or the key work. 2.6 or 3 ft highest 27.0 SECTION. 10.f Trench now sinking 15.ft Surface Water This Section will explain where the water is making its escape through the key work about nine feet at least below the level of surface water above the dam, and as no alteration has yet taken place in its position, or no additional leaks burst out above the points there represented, I am inclined to think it will be found to get through the puddle at abutment, in which case, I request your instructions as to the means you wish. to be adopted, permanently to protect the line of puddle at that point; for any attempt to choke the numberless fissures in the rock would, in my humble opinion, be attended with no hope of success. 3.10 I have the honour to inform you, that the dam at Old Sly's seems perfectly secure, no water gets through it at any part. The (A.) key work across the gap at east abutment, which was the original waste channel, has been carried up to the same height as the rest, and the water completely stopped by the puddling behind it. The old coping has been replaced by another substantial course the whole length of the dam, and is now leveling off with a coping at that height. I have given directions to Mr. Richardson to continue raising the clay parts, and he has been extremely since the alarm at Smith's Falls, making every preparation and using every precaution to resist any sudden rush of water that would come down in the event of a breach being made through the dam at Smith's Falls; and I see no reason to apprehend any danger at Old Sly's. The waste weir carries off the surplus water of the floods. The rise of the river since 13th instant by 5 inches having gradually risen by inches only. Anxious to receive your instructions, P. S. 23d April 1829.-Having visited the work at Smith's Falls early this morning, I found it much in the same state as yesterday, the water through the key work not abated, coming through occasionally coloured by the earth and thrown in above the dam; level of water above dam has varying scarcely any in height since 21st instant. Trench behind key work sunk about ten feet. I lose no time in dispatching this communication to you. (signed) H. Pooley, L R Eng. Correspondence relative to the Canal Communication in Canada. No. 78. No. 77.-LETTER from R. W. Hay, Esq. to the Hon. J. Stewart, SIR, Downing-street, 28th July 1829. I AM directed by Secretary Sir George Murray to transmit to you the copy of a letter from the Secretary to the Board of Ordnance, stating that it will be necessary to increase the vote for the Rideau Canal to the sum of £.140,000. for each of the years 1830 and 1831, if the work is to be completed in 1831, which the Master General and Board of Ordnance are induced to recommend, both as a measure of importance and very considerable economy; and I am to request that you will submit the same to the Lords Commissioners of the Treasury, for their Lordships' consideration and decision. I am, &c. 1 SIR, No. 78-LETTER from R. Byham, Esq. to R. W. Hay, Esq. &c. &c. &c. Office of Ordnance, 8th July 1829. ADVERTING to your letter dated 12th ultimo, transmitting the copy of a despatch from Lieutenant-General Sir James Kempt, enclosing an abridged Report of the proceedings of Lieutenant-Colonel By on the Rideau Canal to the 1st March last, and statement of the expense which has been incurred upon it to that period; I am commanded to acquaint the Master-General and Board of Ordnance have perused these papers, and they request the attention of Secretary Sir George Murray to the opinion expressed by Lieutenant-Colonel By in his letter of the 20th November last, "that the Canal may be completed on the 12th August 1831, "if he be allowed £. 137,200. in each of the years 1829, 1830, 1831; on this his Lordship and the Board beg to observe, that for the year 1829, £. 130,666. only has been allowed, and that it will therefore require in round numbers £. 140,000. for each of the years 1830 and 1831, if the work is to be completed in 1831, which, as a measure of very considerable economy as well as of great consequence, the Master General and Board of Ordnance would recommend should be accomplished, by the allotment of the required sum of £. 140,000. in each of the two next years. I have, &c. R. Byham. No. 79.-Copy of TREASURY MINUTE, dated 4 August 1829. READ a letter from Mr. Hay, dated 28 July 1829, transmitting, by desire of Secretary Sir George Murray, the copy of a letter from the Secretary to the Board of Ordnance, of the 8th ultimo, stating that it will be necessary to increase the vote for the Rideau Canal to £. 140,000. for each of the years 1830 and 1831, if the work is to be completed in 1831, which the Master General and Board of Ordnance are induced to recommend, both as a measure of importance and very considerable economy. Write to Mr. Byham that My Lords have had before them a copy of his letter of the 8th July last, addressed to Mr. Under Secretary Hay, recommending that a vote for £. 140,000. should be submitted to Parliament for each of the years 1830 and 1831, to complete the Rideau Canal; in which letter Mr. Byham refers to one of the 20th November 1828, from Lieutenant-Colonel By, desiring to be allowed £. 137,200. in each of the years 1829, 1830 and 1831, and My Lords request that Mr. Byham will move the Master General and Board of Ordnance to furnish them with a copy of Lieutenant-Colonel By's letter alluded to, and to favour them with any observations which may have occurred to them upon it, with reference to the Report of the Committee formed by General Sir James Kempt, Lieutenant-Colonel Fanshawe |