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Description of the Great Chimney at St Rollox, Glasgow, and 
of the Climbing- Machine used in examining and repairing a 
Rent in that Chimney at the height of 280 feet. By Lrwis 
D. B. Gorpon, Esq., Professor of Civil-Engineering in the 
University of Glasgow, and LAURENCE Hi. Junior, Esq., 
F.R.S.S.A., Civil-Engineer. With a Plate. Communi- 
cated by the Royal Scottish Society of Arts.* 
The great chimney at St Rollox, Glasgow, was erected in 
order to carry off the muriatic acid, and other gases, escap- 
ing in the works, at such a height that, before the gases 
could fall, they should be so diluted as to be innocuous. 
The peculiar construction of the chimney, viz., a double 
cone, was adopted, in order to maintain the heat of the gases 
as long as possible; and at the same time the internal form 
of the chimney and its dimensions are such, that there should 
be a maximum discharge for the same temperature of the 
ascending column. The chimney perfectly accomplished this 
end; but soon after its erection, the process in which the 
muriatic acid is disengaged, was so conducted, that the whole 
gas is now collected, condensed, and applied to useful pur- 
poses, or run off; and thus the great function of the chim- 
ney’s enormous height is no longer brought into use. 
It may be mentioned, that 120 tons of coals are consumed 
per day in St Rollox works, the whole product of the com- 
bustion of which goes up the great chimney, drawn, in some 
cases, from a distance through flues 400 yards long. The 
chimney was designed with a curved batter, the curve being 
the logarithmic curve; but it was not so built, from some 
error in setting out the work at its commencement, Mr Gor- 
don being at the time absent. 
The following are its exact dimensions :— 
* Read before the Society, and drawings and model exhibited, by 
David Stevenson, Esq., F.R.S.E., V.P.,R.S.S.A., civil-engineer, 9th De- 
cember 1844. 
