( "Tall chimney construction. A practical treatise on the construction of tall chimney shafts ... in brick, stone, iron and concrete" Bancroft, Robert M; Bancroft, Francis J 1885 , Page 33 )
"TOWNSEND'S CHIMNEY,
PORT DUNDAS, GLASGOW,
THE TALLEST CHIMNEY IN THE WORLD."
"Designed and built by Mr. ROBERT CORBETT, Bellfield Terrace, Duke Street, Glasgow, for Mr. Joseph Townsend, Crawford Street, Chemical Works, Port Dundas."
"Dimensions,
Total height from bottom of foundation to top of coping . 468'
Height from ground line to top of coping 454'
Outside diameter at ground line 32'
,, ,, top 13"
"Total brick 1,400,000 7,000 tons for bricks only."
"a total of 1,171 days, which was on an average 1,200 bricks laid per day of ten hours."
"The building operations were suspended from the 15th Sep. to 5th Oct., in consequence of the chimney swaying. During this interval it was restored by No. 12 cuttings, with saws on the opposite side to inclination, as hereinafter mentioned under head of straightening"
"Straightening. On Sept. 9th, 1859, the chimney (height 449') was struck by a gale from the N.E., which caused it to sway. The builder does not attribute this action to the gale alone, but to the pressure of the whole pile on the scaffolding, which was so constructed as not to yield to any pressure caused by settling down. The additional pressure caused by the wind on the lee side of the stalk (the mortar of which was not set) was consequently too great for the scaffolding to bear, and caused the splices of one of the uprights A diagram, No. 6 to give way, making the fibres of the timbers to work into each other by compression. The ends of the bearers B diag. No. 5 were tightly built into the masonry at each staging, which occurred every 5' to 6' ; had a space of say 4" been left over each end of the bearers the stalk would have subsided uniformly, and would possibly have withstood the gale. The builder observed this omission, but too late ; he thinks the deflection commenced at from 100' to 150' from the ground, so that the foundation and heavier portion remained firm. The chimney would have probably fallen had not the process of sawing been commenced promptly and continued vigorously. Even during the earlier part of the process of sawing, Mr. Townsend, who was on the ground the whole time, observed the deflection increasing, but as the sawing progressed he noticed it received a check and the shaft u came to " gradually. The chimney was bent 7' 9" at top from its original position, and was less in height than before it swayed, but when brought back regained its former altitude.
Mr. Townsend made his observations during the sawing- back by taking a position in a room of the works near the chimney where he had a full view of it, and fixing the ends of two pieces of twine to a beam above, he formed them into two plummet-lines in a line with the stalk, and with these alone he directed the adjustment of the colossal mass.
The sawing-back was performed by Mr. Townsend's own men from the inside, on the original scaffolding, which, of course, had not been removed. Holes were first punched through the sides to admit the saws, which were worked in opposite lateral directions from such holes at the same joint. This was done at twelve different heights from the ground line, viz.: 41 81 121 151 171 189 209 228 240 255 277' and 326'. The chimney was brought back in a slightly oscillating manner, and the men discovered when they were gaining by the saws being tightened by the superincumbent weight. It took six men continuously working at the sawing- back four sawing and two watering at a total cost of £400.
Prior to the sawing operations the bolts of the scaffolding were taken out and altered, so as to relieve the pressure on it. This was done to meet the want of a little space over the ends of the uprights, as before stated."
" Completion. For many days after the chimney was brought back to the perpendicular and finished Mr. Townsend invited the public to go to the top, and thousands availed themselves of the opportunity. Parties of two at a time were sent up on a small platform without sides, and having at a convenient height a circular cross-bar, on each side of which one person stood and held on. It was quite dark from the time of leaving the ground until emerging through the hatch at the top. There were always four at the top and two going up ; when they arrived two came down to make room. The machinery used for hoisting visitors and materials was driven by friction gearing, an ordinary strong rope being employed. Between 200 and 300 persons were sometimes waiting at the base of the shaft, so great was the rage to mount the monster " lum," and many waited half a day before ascending"
The Builder , May 4th 1878 , Vol 36 Issue 1839 , Page 461
This may be the most complete telling of the building, and fixing, of the chimney
"The Townsend Chimney, Port Dundas, Glasgow. —The total height of this chimney from foundation to top of coping is 468 ft., and from ground level to summit 454 ft. The history of its construction, and of its threatened failure when nearly completed, is fraught with much interest. The chimney was designed and built by Mr. Robert Corbett, for Mr. Joseph Townsend, Crawford-street Chemical Works, Port Dundas. No piles were used in the foundation, which is on “blue till” or clay, which is as solid and compact as rock. The foundation consists of thirty courses of brick on edge, the lowest course being 50 ft., and the topmost course 32 ft. diameter. The foundation was commenced on July 30, 1857, and finished on August 20 of the same year. The erection of the shaft was con- tinued until November 11, 1857 (excepting from September 3 to October 5, during which period operations were suspended). This closed the first season. The second season commenced on June 10, 1858, and closed on October 16 in the same year, the stalk at the latter date being 228 fi. in height. The third and last season commenced on June 3, 1859, and the coping was laid on October 6 of the same year ; but the work was suspended from September 15 to October 5, in consequence of the chimney swaying. During this interval it was restored by twelve cuttings with saws on the opposite side of the inclination, as detailed hereafter. The inside lining or cone is of 9-in. fire-brick, and about 60 ft. in height, built distinct from the chimney proper, with air-space between, and covered on top to prevent dust from falling in, but built with open work in the four upper courses, so as to allow of air passing into the chimney. The size of the bricks used in the construction of the chimney was 10 in. by 4 in. by 34 in.; and the number consumed was as follows :— Common bricks in chimney ................+6 1,142,532 Composition and firebricks in cone......... 157,468 Total ...... 1,300,000 The bricklayers’ time was:—In 1857, 316 days of ten hours each; in 1858, 431} days of ten hours each; and in 1859, 4234 days of ten hours each, giving a total of 1,171 days’ time occupied in building the chimney, which gives on an average 1,110 bricks built per day of ten hours by each bricklayer. . Besides the above number of bricks used in the chimney, there were also 100,000 used in constructing flues,. The total number of bricks laid in chimney and flues was 1,400,000, the weight of which, at five tons per thousand, is 7,000 tons. The cope is of vitrified till, purpose-made, about 9 in. wide by 3 in. thick, flanged over the wall of the chimney, and jointed with Portland cement. The top of the chimney was struck by lightning some time since, which displaced and threw to the ground some pieces of coping, and upon inspection only one of the flanges was found to be broken. Iron hoops were built in at a distance from the surface of 9 in. at the bottom, and 44 in. at the top, and at intervals of 25 ft. in height. The thickness of the wall of the chimney varies as follows, commencing, of course, at the ground level :— Total 454 ft. from ground line, The height originally contemplated for the chimney was 450 ft.; but when about 350 ft. up it was proposed to add about 35 ft. to the original height, making the total height 485 ft. : hence the increased height of the tenth and eleventh seciigns. But on the completion of the eleventh section this idea was abandoned, and therefore only 20 ft. of the last thickness were added. The chimney was not built by contract, but by day wages, as Mr. Townsend was not quite certain to what height he would carry it, or what deviation might be made in course of construction from the proposed plan. Three different dimensions were calculated by the builder ; those carried out were the greatest of the three. The builder calculates the cost of the chimney and cone (exclusive of iron hoops in the chimney and flues) at from 5,500/. to 6,0001. Mr. Townsend estimates the cost of the whole, including flues, iron hoops, machinery, and scaffolding, at 8,0001. On September 9, 1859, the chimney was struck by a gale from the north-east, which caused it to sway; but the builder does not attribute the action to the gale alone, but to the pressure of the whole pile on the scaffolding, which was so constructed as not to yield to any pressure caused by a slight settling-down. The additional pressure thrown by the wind to the lee-side of the stalk (the mortar of which was not solidified) was conse- quently too great for the scaffolding to bear, and caused the splice of one of the uprights to give way by abrasion, making the fibres of the wood to work into each other. The ends of the planks forming the scaffolding were placed about 5 ft. or 6 ft. apart vertically, and were tightly built into the masonry; but had a little space been left over each, the stalk would have subsided uniformly, and would possibly have withstood the gale. The builder observed theerror, but toolate. He thinks the deflection commenced at from 100 ft. to 150 ft. from the ground, so that the foundation and heaviest portion remained firm. Had not the process of sawing been com- menced promptly and continued vigorously, in all likelihood the chimney would have fallen. Even during the earlier part of the process of sawing, Mr. Townsend observed the deflection increasing, but as the sawing progressed he observed that the deflection got a check, and the chimney came-to gradually. The chimney was 7 ft. 9 in. out of the perpendicular, and several feet less in height than before it swayed ; but when brought back it regained its original height, at which time it was not completed by 5ft. Mr. Townsend made his observations during the sawing-back by taking up his position in a room of the works near by the chimney, where he had a full view of it, and fixing the ends of two pieces of twine to a beam above, he formed them into two plummet-lines in a line with the stalk, and by these alone he directed the adjustment of the colossal mass. The sawing-back was performed by Mr. Townsend’s own men, ten men working in relays, four at a time sawing, and two pour- ing water on the saws. This work was done from the inside on the original scaffolding, which, of course, had not been removed. Holes were first punched through the sides to admit the saws, which were wrought alternately in each direction at the same joint on the opposite inclination, so that the chimney was brought back in a slightly oscillating manner. This was done at twelve different heights fromthe ground line, viz., 41 ft., 81 ft., 121 ft., 151 ft., 171 ft., 189 ft., 209 ft., 228 ft., 240 ft., 255 ft., 277 ft., and 326 ft. The men discovered when they were gaining by the saws getting tightened with the superincumbent weight. It took six men to do this work, at a cost of 4001. Prior to the sawing operations, they had taken out and altered the bolts of the scaffolding, so as to relieve the pressure on it. This was done to meet the want of a little spare space over the ends of the planks built into the chimney, as before stated. The stack is protected from lightning by two copper wire conductors, } in. thick, opposite each other allthe way up, joined to one pike fixed to the chimney, but standing above it, at the top. It was erected by a “Steeple Jack” of Manchester, after the chimney had been put straight. The chimney has been several times struck by lightning, and slightly damaged. It is intended to put three more pikes ut the top, and take the conductor round the chimney from pike to pike, to give a better opportunity for absorption of the electric fluid."
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