'^ibrarg
TALL CHIMNEY CONSTRUCTION.
A
OF
TALL CHIMNEY SHAFTS,
CONTAINING
= OF EIGHTY EXISTING MILL, ENGWE-
DETAILS OF UPWARDS OF E^H ^ „^„^^ CHIMNEYS
â– \\^rs^^::^ CEMENT VVORl^^j i"^^^^
HOUSE, BRICK WORKS, CEM ^^^ ^^.^ CONTINENT,
IN ENGLAND, AMERICA AND THE
CONSTRUCTED IN
BRICK, STONE, IRON AND CONCRETE.
BY
ROBERT M. BANCROFT
(Past President Liva
AND
FRANCIS J. BANCROFT
(Assistant Munieipal Surveyor).
— — 8174
Manchester: street.
« G.B.. J.-SO. S«E.T, HO.M., -O ,00. K.K.
JOHN Calvert, 99. '^^^^^ J
Lewes :
..O CO "EAST SUSSEX NEWS" Oeeices.
Farncombe and CO.,
1885.
[Entered at stationers^ ^all.] ^^^ ^
Tr
LEWES
FARNCOMBE AND CO,
PRINTERS.
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Tall Chimney Construction.
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THE Authors wish to state that it has been their aim
throughout to place before the reader a practical
treatise, and for that purpose have collected information
respecting upwards of eighty chimney shafts — brick, stone,
iron and concrete — from various parts of Great Britain, the
Continent and America, and they take this opportunity of
thanking their numerous friends for the uniform courtesy
with which their enquiries have been answered.
In January, 1878, a paper on Chimney Construction
was read by Mr. R. M. Bancroft, Past President, before
the Civil and Mechanical Engineers' Society, and the
interest with which it was received led him to further his
investigations. In December, 1883, a paper on the same
subject was again read before the Civil and Mechanical
Engineers' Society, by the Authors, the information and
examples having been greatly increased. Since that date
the work has been added to, revised and further illustrated.
/'3/0I4
ILLUSTRATIONS,
Plate I.
No.
1 Draught.
2 Wind Pressure.
3 Stability.
4 — 7 Port Dundas, Glasgow. Section at Foundation, Scaffolding, Brick Coping.
8 — 9 St. RoUox, Glasgow. Sectional Plan and Elevation at Foundation.
Plate 2.
10 Barmen, Prussia, Messrs. Wessenfields' Shaft. Cutting Bricks for Straightening.
II — 15 Carlisle, P. Dixon. Sectional Elevation, Plan, Elevation at base of Shaft, Cap
at top.
16 Greenliithe, I. Johnson. Sectional Elevation at base.
Plate 3.
1 7 Dundee, Cox Brothers. Elevation of Shaft.
18 Bradford, Messrs. Lister, Manningham Mills. Part Elevation.
19 — 20 West Cumberland Haematite Works. Plan and Elevation at base.
21 Lancaster, Storey Brothers. Part Elevation and Section at top.
Plate 4.
22 — 30 Bradford, Newlands Mills.
Plate 5.
31 — 33 Dovercourt, Pattrick & Sons. Elevation at base and Cross Sections.
34—36 Northfleet, Messrs. Gosthng. Sectional Elevation, Cross Section and Plan of
Cap.
37 — 38 U.S.A., Cleveland RoUing Mills. Wrought Iron Shaft, Elevation and Cross
Section
39 Prussia, Georgs-Marien Iron Works. Section.
Plate 6.
40 — 43 Dundee, Dens Works. Part Elevation, Vertical Section and details of Cap.
44—47 U.S.A., Falls River Print Works. Part Elevaliun, Vertical Section, details of
Cap and Cross Section.
iv. Illustrations.
Plate 7.
No.
48 — 53 Huddersfield, Brooks & Son. Half Plan at Foundation, Sectional Elevation at
base, Sectional Plan at Flues, Cross Sections and Plan at top.
54 — ^f) U.S.A., Philadelphia Railway Workshops. Elevation, part Vertical Section,
Cross Sections and detail of Cap.
Plate 8.
60 — 64 U.S.A., Yale Lock Co. Elevation at base. Vertical Section, Cross Sections
and Plan at top.
65 — 68 London, South IMetropolitan Gas Works. Vertical Section, Elevation at top
and Cross Sections.
Plate 9.
69 Lewes, IMessrs. Hai-vej', Brewers. Elevation of Octagonal Shaft.
70 — 71 Sunderland, River Wear Commissioners. Elevation and Vertical Section of
Concrete Chimney.
72 — 73 Middlesboro'. Taking down Chimney, Vertical Section and detail Joint of Aii -
tight Spout.
Plate 10.— CAPS.
74 Salford Sewage Works 156' high
75 London, London and North Western Railway Goods Station 150' ,,
76 Eastbourne Water Works 150' ,,
77 London, Messrs. Gordon, Brewers 100' ,,
78 Franlcfort, Messrs. Moulson & Co 92^' ,,
79 London, Great Northern Railway Goods Yard 91^' )»
80 Kent Water Works 90' i>
81 Derby, Great Northern Railway Engine House 90' ,,
82 Hastings, Water Works 84^' „
INDEX.
Page
Illustrations (List of).
General Remarks.
9 — Foundations, Weather, Brickwork, Bond, Expansion,
Supervision, Caps, Cornices, &c.
12 — Minimum Heights of Shafts.
13 — Metropolitan Board of Works Regulations.
Tests and Strength of Materials,
14 — Bricks, Mortar, Stone and Portland Cement.
26 — Draught.
30 — StabiUty.
Height from
cround line _ ^
to top in Existing Chimneys.
feet. When Built.
33 — 454 — Glasgow, Port Dundas J. Townsend — 1857-8-9
37 — 436^ — Glasgow, St. Rollox Teniiant 5f Co. — 1841-2
40 — 367 — Lancashire, Bolton Dohson Ss' Barloiu — 1842
41 — 331 — Prussia, Bamien Wessenjield &■Co. — 1867-8
45 — 329 — Edinburgh Gas Works
47 — 315 — Huddersfield . . . Broohs ^ Son, Fire Clay Works
48 — 312 — Smethwick Adam's Soap Works — 1835
49 — 300 — Carlisle P. Dixon 6^ Sons — 1835-6
50 — 300 — Bradford Mitchell Bros. —
51 — 300 — Halifax J. Crossley iS^ Sons — 1857-8
51 — 297 — Kent, Greenhithe I. C. Johnson —
53 — 282 — U.S.A., Lowell, Mass. . . Merrimack Manufacturing
Company — 1 882
54 — 282 — Dundee Cox Bros. —
56 — 280 — France, Creusot Schneider 6^ Co. — 1869
58 — 259 — Lancashire, Barrow-in-Furness . . Hamatite Iron and
Steel Works — 1865
58 — 255 — U.S.A., Manchester, New Hampshire . . . Amoskeag
Mannfacturing Company — 1883
59 — 256I — Bradford, Manningham Mills Lister dx' Co. — 1872-3
60 — 250 — West Cumberland Hamatite Iron Works
63 — 250 — Lancaster Storey Bros. — 1876-7-8
65 — 245 — Cheshire Connahs Quay Chemical Company
65 — 240 — Bradford Newlaftds Mills (fell down) — 1862-3
68 — 233 — U.S.A., Lawrence, Mass Pacific Mills — 1873
69 — 230 — Harwich, Dovercourt Pattrick & Sons — 1883
70 — 223I — Woolwich Arsenal Shell Foundry
vi. Index.
Height from
ground line
to top in
Page feet. When Built.
71 — 220 — Northfleet J. C. GostUng &• Co. — 1873
74 — 217 — U.S.A., New York .... Steam Heating Company
75 — 210 — Dewsbury Olroyd ^ Sons — 1869
76 — 210 — Lanarkshire Colt ness Iron JVorks
-6 — 190 — U.S.A., Cleveland . . . Ohio Rolling Mills Company — 1881
-8 _ 186 — Sheffield, Deepcar Fox &^ Co. — 1866
y8 — 180 — Buiy Corporation Works — 1881
■jg — 180 — Bradford Corporation Works — 1880
f 180
120 / 1857
80 < 102 )■Prussia, Georgs Marien — 1870
I 102
( 102
174 )
135 > Dundee, Dens Works Baxter Bros.
I02f )
84 — 177 — Crossness Metropolitan Board of Works — 1863-5
85 — 1 70 — Woolwich Gim Factory
85 — 160 — U.S.A., Massachusets . . . Falls River Print IVor/cs
87 — 160 — AVorcester Brick Works TV. D. Barl-er — i86g
88 — 160 — London, Nine Elms Cement Works . . Francis &> Co. — 1878
89 — 160 — Mexico Cotton Factoiy
90 — 158I — Russia, Mr. Shekolden's Paper Mills — 1874
91 — 158 — Abbey Mills Pumping Station . . Metropolitan Board
of JVorks — 1867
92 — 156 — Salford Corporation — 1883
93 — 150 — U.S.A., East Newark, N.J., Mile End Spool Cotton Mill
95 — 150 — Eastbourne Waterworks — 1881-2
95 — 150 — London, Bermondsey .... Prockter ^^ Bevingtoti — 188 1-2
96 — 150 — London, Broad Street Goods Station, City, London and
North- Western Railway — 1867
97 — 150 — Huddersfield Brooks &' Sons — 1878
98 — 140 — Great Yarmouth F. Lacon (^ Co. — 1838
99
'^-^ [ Glasgow McFaiiane &= Co. j ^^73
99 — 133 — Oldham .... Carbon Fertilizer Manure Company — 1874
100 — 127 — Great Yarmouth, Silk Crape Company . Grout &' Co. — 1829-30
lor — I2i| — U.S.A., West Philadelphia Shops, Pennsylvania Railroad
102 — 120^ — Woolwich Arsenal
102 — 120 — London, Clerkenwell Road Re id ^^ Co.
103 — 120 — XJ. S. A., ?>t^mioxA,Co\-i\\Qc{\.c\xi, Yale Lock Manufacturing
Company — 188 1
107 ] Qo [ Birmingham, Hansworth .... Phccnix Bolt Works — 1871
107 — 1083- — Surrey Commercial Docks — 1883
108 — 108 — London, South Metropolitan Gas Works — 1862
109 — 107 — Tamworth Water Works — 1880
no — 105 — Lincolnshire, Boston Flour Mills — 1869-70
111 — 100 — London, Caledonian Road . . . A. Gordon dr» Co. — 1867
112 — 100 — Doncaster Local Board
113 — 96-} — London, Farringdon Street, City, Great Northern Railway — 1880
Page
feet.
114 —
91
115 —
90
116 —
90
117 —
90
118 —
85
119 —
80
120 —
78
121 —
75
121 —
70
122 —
70
122 —
5t'^
124 —
56
76
88 )â–
90
121
125 —
126 —
I?2
Index. vii.
Height from
ground line
to top in
When Built.
— London, Drummond Road . . . Peah, Frean &;' Co. — 1 866
— Manchester Thos. Hoyle 6^ Sons
— Bradford, Great Northern Railway — 1875
— Kent Water Works • . . — 1879
— Loughborough G. Tucker ^r" Son — 1873
— London, Fulham . . . West End Laundry Company — 1883
— Hastings and St. Leonards Electric Light Company . . — 1882-3
— Tunstall Ravensdale Iron Works
— London, Bennondsey G. M. Hatnmer — 1882
— Lewes Harvey ^^ Sons — 1881
— Sunderland, River Wear Commissioners — 1873
— Middlesboro', Taking Down Chimneys
Wrought Iron Chimneys.
Straightening Shafts.
Bingley near Bradford.
Pitchcombe, Gloucestershire. Matthew (Sr* Sons Chemical
Works — 1862
See also p.p. 36, 43, 64 and 67.
Fall of Shafts.
127 — 165 — Oldham A. Stott 6^ Sons — 1873
128 — 100 — Glasgow Waggon Works
128 — 105 — Bury • Eaton Vale Bleach Works
129 — — Sheffield and Neighbourhood, 10 Chimneys. See also
Gostling's and Newlands Mills Chimneys, p.p. 71, 65
Blowing Down Shafts.
130 — 95 — Dublin .... North Lotts Glass Bottle Company — 1820
131 — 406 — Warrington Muspratf s Chemical Works
Moving Shafts.
132 — 78 — U.S.A., Maine Cabot Company's Cotton Mill.
Climbing Chimneys.
132 — — Apparatus employed and instances of Shafts ascended.
Ventilating Shafts.
134 — — For Sewer Ventilation, Towns where adopted.
General.
135 — — An Awkward Dilemma.
136 — — A Novel Dinner Party.
TALL CHIMNEY CONSTRUCTION,
References : W. J. M. Rankine, R. Wilson, Thomas Box, R. Armstrong,
HoLYROYD Smith, P. Carmichael, R. Anderson, Graham Smith,
D. KiRKALDY, H. FAIJA, J. WaUGH.
CHIMNEYS are constructed principally for two purposes.
Firstly, to create the necessary draught for the com-
bustion of fuel ; Secondly, to convey the noxious gases
to such a height that they shall be so intermingled with the
atmosphere as not to be injurious to health.
A chimney shaft, when in work, contains a tall column of
heated air, which, being lighter than the outside atmosphere, is
forced upward by a corresponding column of atmospheric air
pressing into the entrance of the furnace ; thus a displacement
of hot air is constantly being effected, and its place filled by
normal air forcing itself through the furnace of the boiler,
which air is in its turn heated and displaced. The column of
atmospheric air and the column of rarefied air in the chimney
are somewhat like a pair of scales, or the two ends of a lever
of which the boiler is the fulcrum.
Fotindations, — In building large chimneys one of the most
important points is the construction of the foundation. Very
much will depend, of course, upon the nature of the ground.
When on solid rock, it is only necessary to excavate to such
a depth that the heat of the gases will not materially affect
the natural stone, and to a depth sufficient to allow the necessary
spreading of the base. In many instances, however, chimney
stacks have to be built near rivers and on sites where the upper
strata are of alluvial clay or made ground, and it is necessary
to carry the foundation deep down until a stiff clay, hard sand,
or rock bottom is reached. This frequently entails excavation
25' or 30' deep or even more, and it is not only requisite
that the foundation should be large enough to carry the super-
incumbent weight, but also that it should be of such an area
B
10 Tall CJiimney Construction,
that it will not allow the base to be forced into the yielding-
ground. These deep foundations are usually constructed ot
concrete. In some cases piles are driven in to form the founda-
tion, as, among others mentioned further on, in a brick chimney
erected at Boston, England, and in an iron chimney constructed
at Ohio, U.S.A. This piling is a measure on which the engineer
must "decide upon the advisability of using, so as to economise
material without risking unequal subsidence, which cannot be
too carefully guarded against ; and, in fact, it is the practice
in the erection of tall stacks to construct the foundation and
pedestal, if any, and allow them to stand some considerable
time before proceeding with the shaft proper, in order that the
work may set, and any slight settling take place, before a great
weight is built upon it. As a remarkable instance of the general
settlement of the foundation of a shaft, we may mention a
chimney which was built by Mr. Clegg, at P'ulham, over a
quicksand, in which an iron rod sank to a depth of 15' with
little more than its own weight as pressure. During the erection
the concrete foundation sank bodily i' 45" without cracking
the shaft or causing it to deviate from the perpendicular. From
this it will naturally follow that in all cases the ground at
the foundation should be equally resistant, or unequal settling
will take place, as in the disastrous case of the Newland's
Mill chimney, Bradford, as hereinafter detailed. Some of the
pressures exerted upon the foundations are given under the
respective descriptions of the chimneys, most of the other
pressures can be w^orked out from the data supplied.
WcafJicr. — Shafts should be erected in the summer months;
on no account should the work be proceeded with in frosty
weather.
Progress. — Shafts should be constructed at the rate of from
2' to 2\' in height per day, but of course the progress is
largely dependent upon the size of the shaft being erected ; the
taller the shaft the more care should be exercised in allowing
the mortar to set, and the foundations to gradually take and
settle down to the weight of the superincumbent mass. In
Lancashire large shafts are built about half their ultimate height,
and then left six months to consolidate before completion.
Brickwork^ &c. — The bricks used should be picked stocks,
hard and sound, with square sharp edges, thoroughly burnt and
General Remarks. 1 1
of uniform thickness. They should be well wetted with water
before being laid.
The joints of the brickwork should be well flushed up with
mortar every course ; this is much to be preferred to grouting every
2nd or 3rd course. The grouting being fluid mortar becomes
porous and possesses little adhesive power, as the water evapo-
rates. Grouting should, therefore, be discountenanced.
The brickwork should be laid in mortar for the most part
because cement is destroyed by a strong heat. Any l\\" work
at the top should, however, be constructed in good cement.
With so thin a wall the heat is rapidly carried off by the
external air, and in such a case the cement will be uninjured.
Ordinary stock bricks will withstand a heat of 600"; where
a heat is anticipated greater than this, fire-bricks should be used.
Bond. — In large factory chimney shafts the longitudinal
tenacity which resists any force tending to split the chimney is
of more importance than the transverse tenacity ; therefore, in
these structures, it is advisable to have, say, three or four courses
of stretchers to one course of headers.
In some circular stacks an uniform header bond is adopted
for the outside courses of the brickwork. This is a practice
condemned by some authorities, but is almost unavoidable in
the construction of small circular shafts, unless purposely made
bricks are used, owing to the sharp curvature of the work ; in
shafts having large diameters it should never be employed.
The longitudinal strength of a shaft is much increased by
building in hoop-iron every few courses, and is a practice often
adopted and to be commended. Care must, however, be taken
to fix a good lightning conductor to a shaft thus constructed, as
the stack would form a great attraction to the electric fluid.
Expansion. — Chimney shafts should not be tied to any other
work or buildings, and should have no woodwork or anything
fixed to them, on account of the settlement that takes place
after the shaft has been erected, the expansion caused by the
heated gases, and the oscillations caused by wind.
Snpervi'sion. — The shafts should be plumbed and levelled
every 3', or oftener, so as to obtain a regular batter, and keep
the stack erect ; and care should betaken that in angular shafts
the quoins are built without twist.
12 Tall Chimney Construdioii,
Caps, Copings and Cornices. — The stone coping or cornice of
a chimney will seldom require more to hold it together than
two good cramps across each joint ; they should be of copper,
or double dove-tailed slate dowels. On no account should iron
cramps be used, as they will oxidise and burst the stone.
Heavy and large caps are often the source of great danger,
inconvenience and expense (see Brooks & Son's Chimney, page
48), as the cap at top in a gale of wind acts upon the shaft as
a weight at the end of a long lever. The cap, when finished,
should be a complete whole, or so bound together that the joints
cannot open, and be so proportioned that the centres of gravity,
of its respective component parts, all fall within the outer circle
of the shaft on which they rest, and the cap should be designed
so that the wind striking against it is deflected upwards.
A[i)ii)muii HeigJit. — The minimum height of chimney shafts
allowed by many Town Improvement Acts, as in Manchester,
Bradford, Leeds and other towns, is 90'.
FURNACE CHIMNEY SHAFTS,
Metropolitan Board of Works Regulations.
Every chimney shaft, for the furnace of a steam boiler,
brewery, distillery, or manufactory, shall be carried up through-
out in brickwork and mortar, or cement, of the best quality.
Every furnace chimney shall be built upon a bed of con-
crete, to the satisfaction of the District Surveyor.
The base of the shaft shall be solid to the top of the foot-
ings, and the footings shall spread equally all round the base
by regular offsets to a projection on both sides equal to the
thickness of the wall at the base.
The width, measured externally, of a furnace chimney shaft
at the base, or at that portion immediately above the footings,
shall be as follows : —
If square on plan, at least one-tenth of the total height of
the shaft.
If octagonal on plan, at least one-eleventh of the total
height of the shaft.
If circular on plan, at least one-twelfth of the total height
of the shaft.
Ever}'- furnace chimney shaft shall have a batter of ly at
least in every lo' of height, or i in 48.
The brickwork shall be at least 8^" in thickness at the top
of the shaft and for not exceeding 20' below, and shall be in-
creased at least 4I" in thickness for every 20' of additional height
measured downwards.
No portion of the walls of a furnace chimney shaft shall be
constructed of fire-brick, and any fire-brick lining to be used
must be in addition to the thickness of, and independent of, the
brickwork.
Every cap, cornice, pedestal, string-course, or other varia-
tion from plain brickwork, shall be in addition to the thickness
of brickwork prescribed by the foregoing rules, and no cornice
shall project more than the thickness of the brickwork at the
top of the shaft.
TESTS AND STRENGTHS OF MATERIALS.
(Except where otherwise stated, made by D. Kirkaldy, London.)
BRICKS.
Mr. J. C. Edwards' Brick Works, Ruabon,
The following are results of experiments to ascertain the
resistance, to a gradually increased thrusting stress, of twelve
bricks manufactured at these works : —
Description.
Dimensions, inches.
Base area,
square inches
Stress in pounds when
Cracked Craclceil
slightly. 1 generally.
Crushed,
steel-yard
dropped.
Red Brick (no
3-10 . 8-75 X 4-28
37-45
336,050
446,700
461,500
recess)
„
3-13 • 8-75 X 4-26
37-27
225,300
391,500
455,100
>>
3-10 . 8-8o X 4-30
37-84
358,500
408,100
442,950
,, ,, ),
3-19 • 8-78 X 4-26
37-40
215,100
236,250
376,900
,, ), ',
3-IO . 8-75 X 4-28
37-45
232,500
286,100
358,600
>, )) ),
3-15 • 8-73 X 4-29
iSIean . • . .
Lbs. per square in
Tons per square fc
37-45
168,250
223,500
271,300
37-47
255,950
333,025
394,391
ch . .
)0t . .
6,830
8,887
10,525
439-2
571-5
676-8
Blue Bricks (no
3-02 . 8-99 X 4-37
39-28
307,100
385,100
388,050
recess)
)) >) ,,
3-00 . 8-97 X 4-34
38-92
261,900
338,100
377,030
,> )) J,
3-03 . 9-00 X 4*37
39-33
148,300
246,250
344,100
), ), ),
3-05 . 9-00 X 4-38
39-42
181,800
251,500
327,700
„
3-04 . 8-97 X 4-33
38-84
153,000
286,100
310,100
„
3-01 . 8-95 X 4-36
Mean . . . .
Lbs. per square in
Tons per square fc
39-02
258,600
300,200
302,050
39-13
218,450
301,208
341,505
ch . .
)0t . .
5,582
7,697
8,727
358-9
494-9
561-2
Bedded between pieces of pine J" thick.
Tests and Strengths of Materials.
15
High Brooms Brick Company, Tunbridge Wells.
The following table gives the average pressure in pounds
on a single brick, each result being the mean of six tests : —
•-.•..• Base area
Description. 'square inches
Slightly
cracked.
lbs.
Generally
cracked.
lbs.
Crush'd, steel
vard dropped.
lbs.
Tons per
square loot.
Sewage Bricks (dark) . .
Do. do. (light) . .
Brindle do. (dark) . .
Do. do. (light) . .
Blue do
Wire-cut do
Common Building . . .
39-87
39-99
36-97
36-52
40-64
40-80
37-94
170,847
136,933
162,497
94,922
188,125
105,658
74,987
226,853
209,905
211,190
141,688
250,950
157,927
97,070
253-398
232,863
296,790
235.585
332,043
232,337
118,825
408-7
374-5
516-2
414-8
525-4
366-2
201-4
The samples were bedded between pieces of p'.ne j]-" thick.
Staffordshire Vitrified Blue Bricks.
Size of bricks, 2-55" x 9'03" x 4*30".
Mean base area of six samples, 39*06 square inches.
All samples bedded between pieces of pine Y' thick.
J. Hamblett, West Bromwich.
Cracked slightly.
Stress in lbs. when
Cracked generally.
Crushed, steel-yard
dropped.
1st sample
2nd ,,
3icl „
4th „
5th „
6th „
187-5
164-3
153-0
148-2
124-6
II5-8
341-6
306-0
291-0
285-4
244-1
2l6-2
449-68
404-27
396-16
387-82
382-75
366-34
Mean
148-9
280-7
397-83
Equal to lbs. per sq. inch.
,, Tons per sq. foot
3-812
245-1
7-186
462-1
10-185
654-9
i6
Tall Chimney Construction.
The following table gives results of tests made during the
erection of Blackfriars Bridge : —
Bricks in Piers Four Courses high.
Description of bricks.
Size of pier
in l)ricks.
Mortar.
Failing slightly.
tons per foot
super.
Entirely crushed
tons perYoot
super.
Common Stock, recessed .
i^x a
Lias Lime.
17
27
Do. do. . .
,, !I
,,
21
30
Red bricks, machine made
,, ),
,,
20
40
Do. hand made . .
,, ,,
,,
20
3(>
Gault
), ),
Roman Cement
24
59
Do
I X I
,,
54
72
Clark's Sudbury Macliinc .
,, ),
Portland.
49
76
Uxbridge red, hand made .
,, ,)
))
44
53
D. W. Barker's Brick Works, Worcester.
Samples of bricks used in the construction of chimney
shaft 1 60' high at the above works : —
Description.
Pressed, recessed
top and bottom
Dimensions in inches.
3-20 X 9-14 X 4-50
Base area in
square inches
41-13
Mean