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Full text of "Illustrated Catalogue (home edition) of Surveying Instruments, etc"

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MESSRS. 



T. COOKE & SONS 

(LIMITED) 

Illustrated Catalogue 



(HOME EDITION) 

OF 



Surveying Instruments, 

ETC. 

Separate Catalogues of Astronomical and Drawing Instruments, 
and Drawing Paper may be had on application. 



19OT. 








4 

^,_- t 4*- it *""* 






X* ISS2 






NS 





Head Office : Facto* 

14, GREAT CHAPEL STREET, BUCKINGHAM WORKS. 
WESTMINSTER, LONDON, S.W. YORK. ENGLAND. 

Telegrams: "Coordinate, London." Telegram*: "Coordinate, York." 

Branch Office :-i8, STRAND STREET, CAPE TOVvN. 

Telegrams: "Coordinate, Cape Town." 

AGENCIES : 

Johannesburg - - PARGITER & CO. Shanghai - - ILBERT & CO. 

Bulawayo - - - SMART & COPLEY. Calcutta - - TH ACKER & CO. 

Wellington - - ADAMS ENGINEERING CO. 

A. B,C. Code, 4th Edition. 



All Prices in our previous Catalogues are hereby cancelled. 
MESSRS. 

T. COOKE > SONS 

(LIMITED) 

Illustrated Catalogue 



(HOME EDITION) 

OF 



Surveying Instruments, 

ETC. 

Separate Catalogues of Astronomical and Drawing Instruments, 
and Drawing Paper may be had on application. 



190T. DEC 

istz 



V 1 I tr i ft** x 

Head Office: Factory: 

14, GREAT CHAPEL STREET, BUCKINGHAM WORKS, 
WESTMINSTER, LONDON, S.W. YORK, ENGLAND. 

Telegrams: "Coordinate, London." Telegrams: "Coordinate, York." 

Branch Office :-i8, STRAND STREET, CAPE TOWN. 

Telegrams: "Coordinate, Cape Town." 

AGENCIES : 

Johannesburg - - PARQITER & CO. Shanghai - - ILBERT & CO. 

Bulawayo - - - SMART & COPLEY. Calcutta - - TH ACKER & CO. 

Wellington - - ADAMS ENGINEERING CO. 

A. B.C. Code, 4th Edition. 



PACKING AND CARRIAGE OF ALL GOODS CHARGED EXTRA. 
Goods forwarded at Purchaser s Risk. 



YORK: 

COULTAS & VOLANS, ELECTRIC PRINTING WORKS, LITTLE STONEGATE. 







NOTE. 



HTHE prices quoted in this Catalogue are for goods delivered at 

Buckingham Works, York, unless the goods are in stock 

at the London Office of the Company, No. 14, Great Chapel Street, 

Westminster, in which case delivery can be taken there if preferred. 

Should any article ordered be out of stock, it will be supplied 
with the least possible delay. 

Messrs. Cooke &> Sons have had considerable experience in 
supplying complete outfits to Engineers, Surveyors, Explorers, 
Prospectors, Miners, and others, and will be pleased to advise any 
such as to the choice of the most suitable instruments and apparatus 
for any special purpose. They can, and do frequently, supply a 
large variety of other goods in addition to those here catalogued, 
and will obtain to order anything that may be required on receipt 
of full particulars. 

The cost of packing, except in the case of small articles which 
can be easily sent by post, is not included, but special quotations, 
including tin -lined cases, if required, and delivery free on rail or on 
board ship, may be had on application. 

The greatest care is taken in the packing of all goods, but 
Messrs. Cooke &= Sons cannot be held responsible for damage done 
in transit. They suggest that in the event of any goods being received 
in an unsatisfactory condition, an immediate claim should be made 
against the carriers. 

Messrs. Cooke &> Sons employ at their South African Branch, 
18, Strand Street, Cape Town, a staff of workmen specially trained 
in their factory at York, England, capable of effecting Repairs and 
Adjustments to any class of instrument in the shortest possible time. 



T. COOKE & SONS, LIMITED, 



THEODOLITES. 




Fig. 1 



No. 
I. 



Mountain Theodolite. 

(Shown with ^-Screw Adjustment}. 

MOUNTAIN THEODOLITE, of lightest possible construction, with 
open pattern standards, horizontal circle 4-in. dia., reading by two 
verniers to i ; glass protecting covers to verniers. Vertical circle 3-in. 
dia., fitted with metal guard, and reading by vernier to i . Level on 
telescope and two others on plate. Telescope of 875-^. aperture and 
5-in. focal length; two Ramsden eye-pieces, powers 10 and 15 (or one 
erecting eye-piece, power 12 if preferred). Circular compass with 24 -in. 
needle. Two suncaps, sunshade, hand magnifier, plumb-bob, screw 
drivers and levers. Supplied with three levelling screws unless four 
are specially desired. Packed in a mahogany case with shoulder strap. 
Framed telescopic tripod, 5 It. long when open, 3 ft. when closed. 
Weight of instrument, under 4 Ibs.; box and accessories, 4^ Ibs. ; 
tripod stand, 5^ Ibs ^"27 os. od. 



LONDON, YOEK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



No. 

2. 



Theodolites. 

4-Inch TRANSIT THEODOLITE, of light construction, with open 
pattern standards, circles divided on silver to 30 , and reading by ver 
niers, two to each circle, to i . Telescope with object-glass i-in. 
aperture and 7-6-10. focal length. Three levelling screws, high and 
low power eyepieces, two suncaps, sunshade, trough compass and 
plumb-bob. Packed in a mahogany case, fitted with a leather shoulder 
strap. Light tripod stand of framed (or solid) pattern ^"30 os. od. 




Fig. 2. 



5-Inch TRANSIT THEODOLITE, with open pattern standards, circles 
divided on silver to 20 , and reading by verniers, two to each circle, 
to 30", (or to 20" if so desired). Telescope with object-glass i*i25-in. 
aperture and 8-in. focal length. Three levelling screws, high and low 
power eye-pieces, two suncaps, sunshade, trough compass and plumb- 
bob. Packed in a mahogany case, fitted with a leather shoulder 
strap. Tripod stand of framed (or solid) pattern, with centering 
arrangement and locking plate ... ... ... ... ^"33 os. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Theodolites. 

No. 

5. 5-Inch TRANSIT THEODOLITE, as above, but with object-glass 

i 35-in. aperture and lo-in. focal length ... ... ^"35 os. od. 

6. 5-Inch TRANSIT THEODOLITE, as above, but with extra large 

telescope, having object glass i-6-in. aperture and i2-in. focal 
length 38 os. od. 

7. 5-Inch TRANSIT THEODOLITE, as No. 4, but without vertical 

circle (Railway pattern) ... ... ... ... ... ^"30 os. od. 

8. 5-Inch TRANSIT THEODOLITE, as No. 5, but without vertical 

circle (Railway pattern) ... ... ... ... ... 32 os. od. 

9. 6-Inch TRANSIT THEODOLITE, divided to 20 and reading 

to 20". Object-glass i 35-in. aperture and lo-in. focal length. 
Tripod stand of framed pattern with centering arrangement. 
Accessories as to No. 4. Packed in two cases, fitted with leather 
shoulder straps ... ... ... ... ... ... 38 os. od. 

10. 6- Inch ,; TRANSIT THEODOLITE, as No. 9, but with object-glass 

i-6-in. aperture and i2-in. focal length ^"40 os. cd. 

11. 6-Inch TRANSIT THEODOLITE, as above, but with extra large 

telescope, having object glass i 8-in. aperture and i3-in. focal 
length ^"43 os. od. 

12. 6-Inch TRANSIT THEODOLITE, as No. 9, but without vertical 

circle (Railway pattern). Packed in one case, fitted with leather 
shoulder strap ... .. ... ... ... ... ^"34 os. od. 

13. 6-Inch TRANSIT THEODOLITE, as No. 10, but without vertical 

circle (Railway pattern) ^"36 os. od. 

14. 7-Inch TRANSIT THEODOLITE, as No. 9, but divided to 15 and 

reading by three verniers to horizontal and two to vertical 
circle to 15". Telescope with object-glass i-6-in. aperture and 
i2-in. focal length. No centering arrangement included. Packed 
in two cases, fitted with leather shoulder straps ... ^"45 os. od. 

15. 8-Inch TRANSIT THEODOLITE, as No. 14, but of heavier con 

struction. Circles divided to 10 , and reading by three verniers 
to horizontal and two to vertical circle to 10". Telescope with 
object glass i 8-in. aperture and i3-in. focal length. Packed in two 
cases, fitted with leather shoulder straps ^"55 os. od. 

16. 10-Inch TRANSIT THEODOLITE, Specification according to require 

ments. 



For particulars of the Adjustments, etc., of these Theodolites see page 85. 



LONDON, YORK AND CAPE TOWN, 



T. COOKE & SONS, LIMITED, 



Theodolites. 




No. 

17- 



18. 



19. 



20. 



Fig. 3. 

TRANSIT THEODOLITES WITH MICROMETERS. 

5-Inch TRANSIT THEODOLITE, with open pattern standards, 
horizontal circle divided to 10 , and reading by two micrometer 
microscopes to 10"; vertical circle divided to 20 , and reading by 
two verniers to 30". Telescope with object-glass i 35-in. aperture 
and lo-in. focal length. High and low power eye-pieces, two 
suncaps, sunshade, trough compass and plumb-bob. Packed in two 
mahogany cases, fitted with leather shoulder straps. Tripod stand 
of framed pattern, with centering arrangement ... ^"40 os. od. 

5-Inch TRANSIT THEODOLITE, as No. 17, but with micrometer 
microscopes to both circles, and reading to 10" ... ^"45 os. od. 

6-Inch TRANSIT THEODOLITE, as No. 17, but with vertical 
circle reading by two verniers to 20", and having telescope with object 
glass i-6-in. aperture and i2-in. focal length ^"45 os. od. 

6-Inch TRANSIT THEODOLITE, as above, but with micrometer 
microscopes to both circles, and reading to 10" ... ^"50 os. od. 



LONDON, YOEK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



No. 
21. 



22. 



23- 



26. 



Theodolites. 

8-Inch TRANSIT THEODOLITE, as No. 20, but of heavier con 
struction, divided to 5 , and reading by three micrometer microscopes 
to horizontal, and two to vertical circle to 5", with additional pointer 
microscopes for reading the figures. Telescope with object glass 
i 8-in. aperture and i3-in. focal length. No centering arrangement 
included ^"75 os. od. 

10-Inch TRANSIT THEODOLITE, as No. 21, but reading to 2" 
of arc by either circle, and having telescope with object glass 2-o-in. 
aperture and about i6-in. iocal length ... ... ... ,"120 os. od. 

12-Inch TRANSIT THEODOLITE, Specification according to require 
ments. 
Estimates given for Theodolites of Special Design or of Larger Size. 

EVEREST THEODOLITES. 




Fig. 4 
Everest Theodolite. (Shown without Centering Arrangement as No. 28.) 

5-Inch EVEREST THEODOLITE, divided to 20 and reading 
to 30". Telescope with object glass 1-125-11). aperture and 8-in. 
focal length. Three screws and locking plate, circles and verniers 
read by simple microscopes, with high and low power eye-pieces, two 
caps, sunshade, trough compass and plumb-bob. Packed in a maho 
gany case, fitted with leather shoulder strap. Tripod stand of framed 
pattern, with centering arrangement ^"31 os. od. 



LONDON, YOEK AND CAPE TOWN. 



8 



T. COOKE & SONS, LIMITED, 



NO. Theodolites. 

27. 6-Inch EVEREST THEODOLITE, as No. 26, but reading to 20", and 

having telescope with object glass i 35-in. aperture and lo-in. focal 
length .36 os. od. 

28. 7-Inch EVEREST THEODOLITE, as above, but reading to 15", and 

having telescope with object glass i-6-in. aperture and i2-in. 
focaLlength. No centering arrangement included. Packed in two 
cases "42 os. od. 

29. 8-Inch EVEREST THEODOLITE, as No. 28, but reading to 10", 

and having telescope with object glass i-8-in. aperture and i3-in. 
focal length ^50 os. od. 

AMERICAN PATTERN THEODOLITES. 



30- 




Fig. 5. 



TRANSIT THEODOLITE, with open pattern standards, flat horizontal 
circle of 6-in. dia., graduated on silver, and reading by two double 
verniers to 20" ; Glass protecting covers to verniers. Vertical circle, 
5-in. dia., fitted with metal guard, graduated on silver, and reading by 
one double vernier to 20". Long level on telescope and two levels on 
plate. Telescope of i*i25-in. aperture and 8-in. focal length, two 
Ramsden eye-pieces, powers 16 and 24, (or one erecting eye-piece, 
power 20, if preferred). Four levelling screws and shifting centre. 
Circular compass with needle 4-in. long, two suncaps, sun-shade, 
and plumb-bob, screwdrivers and levers. Packed in a mahogany 
case, with shoulder strap. Framed tripod ^"35 os. od. 

If with fixed microscopes for reading thejverniers ... 36 os. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



9 



Theodolites. 





Fig. 7. 



Fig. 6. 

32. MINING TRANSIT THEODOLITE, as American pattern No. 30, but 
with additional telescope of -875-^. aperture and 5-in. focal length, 
interchangeable on side and top of the main telescope by means of 
screwed extensions on end and centre of telescope axis, giving a clear 
vertical sight downwards in either position. Diaphragm fitted with 
one cross line, which is horizontal when the telescope is on the side, 
and vertical when on the top of large telescope. The former allows 
angles of depression to be measured, which by reason of the interference 
of the horizontal limb cannot be obtained by the large telescope. Slow- 
motion adjustment and clamp for setting the single cross wire of the 
interchangeable telescope in the same plane as the line of collimation 
of the large telescope. The surveyor by this method has the advantage 
of making his own adjustment, and does not rely upon a fixed adjust 
ment of the makers, the continued accuracy of which in this particular 
case it would be impossible to retain. One Ramsden eye-piece, power 
14, fitted with prism attachment for convenience in vertical sighting. 
Reflectors to fit on object ends of both telescopes for illumination of 
lines. Counterpoise to supplementary telescope in either position. 
Dust guards to levelling screws. Packed in a mahogany case with 
shoulder strap. Telescopic tripod of framed pattern ... ^"43 os. od. 



LONDON, YOEK AND CAPE TOWN. 



10 



T. COOKE & SONS, LIMITED, 



TACHEOMETERS. 




33. 4-Inch TACHEOMETER, with open pattern standards, circles divided 

either} to 30 reading to i , or centesimally to 50 reading to i . 
Telescope with object glass i-125-in. aperture, 8-in. focal length, and 
anallatic lens. Bubble on telescope as well as on vernier arms. Three 
screws and locking plate, high and low power eye-pieces, two suncaps, 
sunshade, trough compass and plumb-bob. Packed in a mahogany 
case, fitted with leather shoulder strap. Light mahogany tripod stand 
of solid pattern, without centering arrangement ... ^"32 os. od. 

34. 4-Inch TACHEOMETER, as above, but with light telescopic tripod 

stand ... ... ... ... ... ... ... ^"33 os. od. 

35. 5-Inch TACHEOMETER, as No. 33, but reading to 30", or 

centesimally to i . Telescope with object glass i 35-in. aperture, 
lo-in. focal length, and anallatic lens. Tripod stand of framed or 
solid pattern, with centering arrangement ... ... ^"36 os. od. 

36. 6-Inch TACHEOMETER, as above, but reading to 20", or 

centesimally to i , and by estimation to o 5 . Telescope with object 
glass i-6-in. aperture, i2-in. focal length, and anallatic lens. Packed 
in two cases, fitted with shoulder straps. Tripod stand of framed 
pattern, with centering arrangement ^"41 os. od. 

37. Kew Certificate to any Theodolite or Tacheometer 16/- and upwards, 

according to size. 

For further information concerning Tacheometevs see page 88. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



ii 



Extras and Additions to Theodolites and 
Tacheometers. 



No. 


ONE CASE. 


Two CASES. 


Best Solid. WWjMt 


Best Solid. 


With Felt 
Lining. 




LEATHER CASES- 


*.** 


s. d. 


i 


s. 


d. 


i 


s. 


d. 


38. 


For 3-in. Instrument ... 


150 i 


14 o 
















39- 


4 , 


I IO O 2 



















40. 


ii 5 ii 


I 13 O 2 


C o 


2 


10 


o 


3 


5 


o 


41. 


D 6 ,, ,, 


I l6 2 


IO O 


2 


17 


o 


3 


15 


o 


42. 


7 i, 








3 


5 





4 


7 





43- 


8 








3 


13 





5 








44. 


ii I0 ii ii 








4 


15 


o 


6 


7 


o 


45- 


Canvas and leather bound 


case for tripod 


... 






.. 


i 


10 





46. 


5J J5 


cap 


head 


... 









7 


6 


47- 


Solid leather 


ii D ii 


,, 


... 






o 


15 


o 




Centering: Head to Solid 
Pattern Tripod. 

Fig. 9. 



Telescopic Tripod with Centering: Head. 

Fig. 10. 

Tripods. 



LONDON, YORK AND CAPE TOWN. 



12 



T. COOKE SONS, LIMITED, 



Extras, etc. 

No. 

Non-Centering. Centering. 

49. TRIPOD STAND of light pattern, for Mountain 

Theodolite ... ... ... ... ... ... 2150 

50. DITTO of solid round pattern for Mountain, and 

of framed or solid round pattern for 4- in. Theo 
dolite 350 

51. DITTO telescopic ... ... ... ... ... 4 o o 

52. DITTO of framed or solid round pattern for 5-in. 

and 6-in. Theodolites ... ... ... ... 3 5 o 

53. DITTO telescopic 500 

54. DITTO of framed pattern for y-in. and 8-in. 

Theodolites ... ... ... ... ... ... 4 5 o 

55. DITTO of framed pattern for lo-in. Theodolite 4 10 o 



4 10 o 
550 

4 15 o 
6 10 o 

650 




Fig. 11. 



57. Centering and levelling arrangement to stand of 5-in. or 6-in. instru 
ments. Figs, ii and 12 ... ... ... ... ... ^3 os. od. 

An allowance of i los. od. will be made when the ordinary centering 
arrangement is already included. 

The prices quoted for centering arrangements are to new instruments 
only ; when supplied to old instruments an extra charge will be incurred for 
fitting. 

No. 5. d. 

59. ILLUMINATED AXIS 35; -, and STRIDING LEVEL i 5 / , to 

5-in. or 6-in. instruments 2 10 o 

60. DITTO 40; - ditto, 2o/-, to 7-in. or 8-in. instruments ... 3 o o 

61. DITTO 5o/- ditto, 3O/-, to lo-in. instruments ... ...400 

62. DIAGONAL EYE-PIECE, with swivel socket i 15 o 

63. EYE-PIECES, Ramsden, high or low power o 12 6 

64. DITTO erecting 176 

65. SUNCAPS, each 030 



LONDON, YOEK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



66. 
67. 
68. 
69. 
70. 



Extras, etc. 

BUBBLES 

For Mountain &4-in. Instruments 



6-in. and 7-in. 
8-in. 
lo-in. 



Small Plate. Large Plate. ^"fe"^ 



8/. 

I2/- 




Fig. 13. 



Fig. 14. 



Fig. 15. 



Fig. 16. 



Diaphragms for Theodolites and Tacheo meters. 

These are of parallel glass and the lines are ruled with a fine diamond ; 
(Spider lines can be had if preferred at the same prices). 

Fig. 13 shows a simple + (as adopted by the India Office) with the addition 
of stadia lines, i in 100 or any other ratio desired. 

Fig, 14 is a pattern frequently supplied, and 

Fig. 15 is an improvement upon it in which no more than two lines cross at 

any one point, thus offering the minimum of obscurity. 
Fig. 1 6 is the standard pattern for tacheometers, the stadia lines being i in 50 

and i in 100, but i in 100 and i in 200, or any other ratios can be ruled to 

order. 



No. 

72. DIAPHRAGMS, ordinary, parallel glass o 

73. DITTO special or stadia lines o 

74. GUN-METAL BLOCK, with dove-tailed slide and adjusting 

screws, for carrying glass diaphragm ... ... ... ... o 

78. SOLAR ATTACHMENT to 5-in. or 6-in. instruments, having 

extra large telescopes 12 

79. DITTO to 7-in. or 8-in. instruments 15 

80. GRADIENTER ATTACHMENT to 5 in. or 6-in. instruments ; 

to either circle ... ... ... ... ... ... ... i 

81. WALL PLATE, for use on masonry pillar, or elsewhere, in 

place of tripod " o 

82. PLUMB-BOBS, gun-metal, with steel point and silk cord, 

8 oz., 3/6 ; 12 oz., 4/6; 16 oz o 

83. DITTO cheaper quality, small, without cord o 

84. DITTO plain steel, with hardened point, without cord ... o 

85. TROUGH COMPASS, for 5-in. or 6-in instruments o 

86. CIRCULAR COMPASS in lieu of trough compass ... 



7 6 



O 

o 

10 
12 

6 

2 

I 



i 10 



LONDON, YORK AND CAPE TOWN, 



14 T. COOKE & SONS, LIMITED, 

Extras, etc. 




Fig. 17. 

No. s. d. 
DIAGONAL REFLECTOR, fitting on O.G. end of telescope : 

87. For 5-in. and 6-in. instruments 076 

88. For 7-in. and 8-in. ,, o 10 o 

EXTRA BUBBLE in tube, fitted on telescope : 

89. To 5-in. and 6-in. instruments 150 

90. To 7-in. and 8-in. ,, ... ... ... ... . . i 10 o 

91. SHORT FOCUSSING ARRANGEMENT by means of a slit 

rendering it possible to take sights much within the usual 

minimum distance o 10 o 

92. LEVELLING SCREWS, each 026 

93. LEATHER SHOULDER STRAP ...036 

94. STRAPS for solid round pattern tripod o i 6 

95. INSTRUMENT OIL, per bottle o i 6 



DIAGRAMS, BOOKS, TABLES, Etc. 

99. GILLMAN S PATENT DIAGRAM, for the rapid reduction 

of Tacheometer readings (360 or 400) ... ... ... 076 

100. STEWART S COPYRIGHT DIAGRAM, giving the hori 

zontal distance and the vertical height direct, without 

any calculation (360 and 400) ... ... ... ... 076 

101. CUARTERO S TABLES (400) i i o 

102. JORDAN S TABLES (360) o 12 6 

103. BEAZELEY S TABLES of Railway Curves, on cards ... 040 

104. FIELD BOOK, size 7-in. by 4^-in., ruled two centre 

lines only, bound red basil, with elastic band ... ... o i 6 

105. DITTO ruled faint lines and centre line 020 

106. DITTO size 8^-in. by 5-in 026 

107. DITTO as No. 104, but of cheaper make, half bound cloth o i o 

108. LEVELLING BOOK, size 7i-in. by 4f-in., ruled and 

headed, bound red basil, with round corners ... ... 020 

109. DITTO of cheaper make, half bound cloth ... ... ... o i 6 

no. TACHEOMETER BOOK, as level book No. 108 020 

in. SECTIONAL RULED NOTE BOOK, oblong, -in. or ^-in. 
square ruling, 100 leaves, bound limp roan, with elastic 
band, size 6^-in. by 4-in 026 

112. DITTO size 7|-in. by 5-in 036 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 15 



SCIENTIFIC AND ENGINEERING BOOKS. 

The Electrical Engineer s Pocket Book Kempe 050 

Electrical Engineering for Electric Light Students Slingo&Broktf o 12 o 

Standard Wiring for Electric Light and Power ... Harrison 046 

"The Electrician" Wireman s Pocket Book ... ... Raphael 050 

Engineer s Year Book ... ... ... ... ... Kempe 080 

Land Area Computation made easy (Amsler s Plani- 

meter) Codd 006 

Railroad Spiral (Theory of Transition Curve)... ... Searles 066 

Handbook Street Railroad Location ... ... ... Brookes 066 

Engineer s Field Book ... ... ... ... ... Skunk o 10 6 

African Pilot (Part 3 South) 050 

Railway Track and Trackwork ... ... ... ... Tratman o 12 6 

Surveying with the Tacheometer ... ... ... Kennedy o 10 6 

Economic Theory of the Location of Railways ...Wellington i i o 

Practical Surveying Usill 076 

Curve Tables ... ... ... ... ... ... Kronkhi 050 

Treatise on Surveying (2 vols.) ea. ... ... ... Gillespie o 10 6 

Do. ,, ,, ... Middleton &* Chadwick o 10 6 

The Steam Engine... ... ... ... ... ... Ewing o 15 o 

Civil Engineer s Pocket Book Trautwine i i o 

Engineering Formulae Pocket Book Molesivorth 060 

Engineers Tables in celluloid case ... ... ... Hurst o i 6 

Mathematical Tables Chambers 046 

Curve Tables ... ... ... ... Kennedy &> Hackwood 026 

Astronomy for Everybody Newconie 076 

Navigation and Nautical Astronomy Martin o 18 o 

Electric Traction Pocket Book ... ... ... ... Dawson o 17 6 

Fergusson s Percentage Theodolite with examples ... Fergusson 006 

Nautical Almanac ... ... ... ... ... 026 

On the Aneroid and Meteorological Instruments ... Cooke 006 

Land Area Tables Codd 036 

Half-hours with the Microscope ... ... ... ... Lankester 026 

The Aneroid Barometer, how to use it ... 006 



LONDON, YORK AND CAPE TOWN. 



i6 



T. COOKE & SONS, LIMITED, 



FERGUSSON S PERCENTAGE SURVEYING CIRCLE, 




Fig. 18. 



FERGUSSON S PERCENTAGE SURVEYING CIRCLE is shown in Fig. 18, 
which illustrates the method of forming Fergussons Percentage Unit of 
Angular Measurement. 

Fig. 1 8 does not shew the degree divisions, which are either marked on 
a separate concentric circle, or a single circle may be used, one half being 
divided in Percentages and the other half in Degrees. 



ADVANTAGES OF THE PERCENTAGE CIRCLE. 

It is a telemeter circle in azimuth and altitude, because every division 
subtends of the base-line. 



It does away with Traverse Tables, as the length of the departure is 
expressed by the number of the angle; thus, the departure in an angle read as 
12%, at a point along the base-line 320 feet from the vertex is simply 12 per 
cent, of 320 feet or 38-4 feet. 

Without tables, the distance, level, latitude and departure of a station 
can be got in the field, and curves of any radius may be ranged instantly. 
This cannot be done by any other instrument^divided in degrees only. 

Fergusson s Percentage Unit is easier to work in than the degree, as it 
does away with tables and trigonometrical formulae. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 17 



When Fergusson s Surveying Circle is attached to a compass or other 
surveying instrument in place of the ordinary dial or circle divided only into 
degrees, the instrument is at once converted into a telemeter or range finder, 
and may be read either in units of degree or in percentage divisions, as 
desired. Problems which would be difficult to solve by trigonometrical 
formulae, when angles are read in degrees, are calculated with ease and 
rapidity by simple arithmetic, and can often be solved mentally, when the 
angles are read in percentage units. 

When a percentage angle is bisected, the half nearer the base-line con 
tains fewer percentage units, or divisions, than the half of the same angle, 
which is farther from the base-line ; thus : 

Take for example, a course of 1,000 feet long, bearing North 80 per cent. 
East ; when the angle of 80 per cent, is bisected, the half of the angle adjacent 
to the base-line, contains 35*055 divisions, and the other half of this angle 
farther from the base-line, contains 44*945 divisions. These two numbers 
express the ratio which the length of the 1,000 feet course (North 80 per cent. 
East) bears to the quadrantal-base-line running due North ; so every 44-945 
feet along the course will contain 35*055 feet of Northing along the quad 
rantal-base-line. 

Therefore the length of the course being 1,000 feet, the Northing is 
781*25 feet, and the departure (or Easting) is 80 per cent, of 781-25 or 625 
feet. In this way, the Latitude and departure of a course measured in any 
direction is immediately established, and the tangent, sine, secant, radius or 
cosine, can be obtained by using these ratios ; for in an angle of 80 per cent. 

44-945 : 35*055 :: Tan. : Sin. 

44*945 : 35 O55 :: Sec. : Rad. 

44*945 : 35*055 :: Rad. : Cos. 

This particular ratio between the percentage units contained in the two 
halves of a percentage angle is of the greatest importance, and has been 
described as "a mathematical discovery of great practical value," for herein 
lies the secret to the solution of all problems in plane trigonometry. 

The easiest method of dividing a percentage angle on the instrument is 
to bisect the equivalent angle in degrees and minutes on the opposite half of 
the circle with the vernier ; and then read the percentage base-half of the 
angle ; this, subtracted from the whole angle, gives the excess half-percentage 
of the angle, and with these two sets of figures the surveyor can at once get 
any function he requires arithmetically. 

A Pamphlet entitled "Fergusson s Percentage Theodolite, with examples," 
may be obtained from Messrs. T. Cooke & Sons, Ltd., post free, i/- 

Any of the Theodolites or Tacheometers listed on the preceding pages 
may be fitted with Fergusson s Percentage Circles at an extra charge. 



LONDON, YORK AND CAPE TOWN. 



i8 



T. COOKE SONS, LIMITED, 




FERGUSSON S STANDARD PERCENTAGE 
THEODOLITE. 



1 19. FERGUSSON S STANDARD PERCENTAGE THEODOLITE (or Survey 
ing Circle), with open pattern standards. Circles 5 inches diameter 
divided on silver. The horizontal circle is divided into two complete 
circles of divisions, one degrees and the other percentage units. The 
vertical circle is divided one half into degrees, the other half into per 
centage units. Fitted with Fergusson s Tangential Micrometer for 
reading at sight the unequal percentage divisions in T -o~ ths > thus affording 
a closer and easier method of reading small fractions of arc than by means 
of a vernier. Telescope with object glass i 35-in. aperture and lo-in. focal 
length, with stadia lines i in 100 and anallatic lens, long level on 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 19 

telescope, high and low power eye-pieces, two suncaps, trough compass 
and tape-suspended plumb-bob. Packed in mahogany case fitted with 
a leather shoulder strap. Tripod of framed pattern with aluminium 
head, centering arrangement and locking plate ... ^"45 os. od. 



[Copy.] THE UNIVERSITY, BIRMINGHAM, 

May 2nd, 1905. 

Fergusson s Percentage Theodolite. 

1 have pleasure in stating that I have examined Fergusson s Percentage Theodolite from 
a point of view of the mathematics involved in its use. and can certify that the claims made on 
its behalf are justified. It has also been tested practically in the field in the Engineering 
Department of this University, and has been found extremely convenient in use. 

The novelty of the instrument consists of a new method of graduation of the horizontal 
and vertical circles of a Theodolite. The circles are divided into spaces proportional to the 
tangents of the angles subtended. The division is complete for each octant, tan 45 being 
called 100. The new graduation is applied, however, only to one half of each circle, the other 
halves of the circles being divided into degrees and minutes in the usual manner. 

By means of the vertical circle and a graduated levelling staff the length of a course can 
be found without calculation whether the line of sight be inclined or not. 

The length of the course being known, the rectangular coordinates of the course can be 
obtained immediately from a reading of the horizontal circle. 

The length of the course being known, the difference of level between the ends of a course 
can be read directly from the instrument. 

In curve ranging, no tables are required for the determination of the deflexion angle. 

The reduction of the results of observations can be carried on simultaneously with the 
field work without reference to books of tables. Thus all the information about any point on 
the field can be known whilst the surveyor is on the spot. 

For all traverse surveying, especially for a rapid preliminary traverse subject to modifi 
cation, the instrument possesses distinct advantages over the ordinary Theodolite. 

(Signed) R. S. HEATH, M.A., D.Sc., 

Professor of Mathematics. 
Vice-Principal of the University. 



LONDON, \OEK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



LEVELS. 




Fig. 19. 



COOKE S PATENT REVERSIBLE LEVEL, with three screws and 
locking plate, cross bubble, high and low power eye-pieces, etc., packed 
in a mahogany case, with leather shoulder strap. Tripod stand of solid 
pattern for lo-in. instruments, of solid or framed pattern for i2-in. and 
i4-in. instruments, and of framed pattern for the larger sizes. See 
page 79. 



No. 


Size. 


With compass 
and prismatic 
reader. 


Without 
compass. 


121 


lo-in. Cooke s Reversible Level ... 


s> d. 
13 oo 


s. d. 

12 IO 


122 


i2-in. ... 


14 o o 


13*10 o 


I2 3 


H-in. ,, 


1600 


15 5 o 


I2 4 


*i5-n- M 


18 10 o 





125 


i6-in. 


1800 


17 5 o 


126 


i8-in. ... 


2O O 


19 5 o 


127 


2o-in. ,, ,, 


22 O 


21 O O 



* With slow motion adjustment, War Office pattern. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



21 



Levels. 




Fig. 20. 



Dumpy Level. 

DUMPY LEVEL of good construction, with three screws, cross 
bubble, high and low power eye-pieces, etc. No compass. Packed in 
mahogany case, fitted with leather shoulder strap. Tripod stand of solid 
pattern. Made in three sizes only. 



No. 

129. lo-in. Dumpy Level 

130. i2-in. ,, ,, 

131. i4-in. ,, ,, 



*- A. 

12 O O 

13 o o 
14 o o 



LONDON, YORK AND CAPE TOWN. 



22 



T. COOKE & SONS, LIMITED, 



Levels. 




133. BUILDER S LEYEL, in one size only, g-in., a useful and 
reliable instrument with three screw adjustment and long 
bubble, packed in a pine case, fitted with leather shoulder 
strap. Light tripod stand of solid pattern 



7 10 o 



Bolton s Patent, Cushing s Patent, or Wye Levels, at prices i in excess 
of those quoted for Cooke s Levels. 



Extras and Additions to Levels. 



No. 



LEATHER CASES 

For lo-in. Level 



i4-in. 



135. 
136. 
137. 
138. 
139. 
140. 
141. 

142. Canvas and leather bound case for tripod ... 

143. ,, ,, ,, ,, cap ,, ,, head 

144. Solid leather ,, ,, 



2o-n. 



Best Solid. 


With Felt 
Lining. 





S. 


d. 


i 


S. 


d. 


I 


3 


o 


I 


14 





I 


6 


o 


I 


18 


o 


I 


9 


o 


2 


2 





I 


ii 


o 


2 


4 


o 


I 


13 


o 


2 


7 


o 


I 


17 





2 


12 


o 


2 


2 


o 


2 


18 


o 


... 




... 


I 


10 









... 





7 


6 


. . . 




. . . 


O 


15 






LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Extras, etc. 

No. s. d. 

145. TRIPOD STAND, ordinary, for lo-in. level 2 10 o 

146. ,, i2-in. or i4-in. do. ... 35 

147. ,, ,, ,, ,, i6-in. or i8-in. do. ... 3 15 o 
H 8 - > 2o-in. do. 500 

149. ,, ,, telescopic, for lo-in. or i2-in. level ... 400 

150. ,, ,, i4-in. do. 4 10 o 

151. ROUGH LEVELLING ARRANGEMENT to stand of i2-in., 

i4-in., or i6-in. level 220 

152. SLOW-MOTION ADJUSTMENT in azimuth to do. ... i 10 o 

153. EYE-PIECES, Ramsden, high or low power o 12 6 

154. DITTO Erecting 176 




Fig. 



<io. 22. 



155. DEACON S PATENT OPTICAL SQUARE ATTACHMENT can be fitted 
to any level, and consists of an attachment A, carrying a prism P, for 
ranging out lines at right angles to the main line, on flat or hilly ground. 
After closing the shutter S the line of sight is deflected through an angle 
of 90, and by revolving the attachment about the object glass O, 
any points in the vertical plane at right angles to the axis of the 
telescope, can be brought into focus without altering the position of 
the level. With the addition of stadia lines to the level tacheometrical 
readings may be taken in all directions at a single setting up of the 
instrument. The presence of the prism in no way interferes with the 
ordinary staff readings ... ... ... ... ... i 55. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



156. 
157- 

158. 

159- 
1 60. 



161. 
162. 
163. 

164. 
165. 



No. 



168. 
169. 
170. 



BUBBLES 

For g-in. Level 
io-in. 



Extras, etc. 



,, i4-in., i5-in. and i6-in. Levels ... 
,, i8-in. and 2o-in. 





Fig. 24. Fig. 25. 

DIAPHRAGMS, ordinary, parallel glass. Fig. 24 

DITTO special or stadia lines. Fig. 25 

GUN-METAL BLOCK, with dove-tailed slide and adjusting 

screws, for carrying glass diaphragm 
LEATHER SHOULDER STRAP ... 
LEVELLING SCREWS, each 

MINING DIALS. 




Cross. 



2 O 

2 O 

2 O 

3 O 



050 
076 



7 6 
3 6 



Fig. 26. 

MINER S DIAL, of best make, a strong serviceable instrument, very 
suitable for rapid surveying, with folding sights and circular bubble ; 
Tripod stand, with ball-and-socket joint : s . d. 

Diameter of box, 6-in 8 10 o 

Ditto, with 5-in. box of aluminium, very light 800 

Divided cover to either of above, giving difference of 
hypothenuse and base ... ... ... ... ... o 15 o 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



No. 

171. 

172. 

*73- 

174. 



178. 

179. 
1 80. 
181. 
182. 
183. 



Mining: Dials. 

IMPROVED MINER S DIAL, with semi-circular vertical arc, which 
can be folded down when not required ; Folding sights, two 
level bubbles, etc. ; packed in a mahogany case. Tripod stand with 
legs jointed in the middle, and ball-and-socket joint. 



Diameter of box, 5-in. ... ... ... ... ... ... 16 



Ditto 6-in. 
Telescope fitted to either of the above, extra 
Solid leather case to box of mining dial, 5-in. or 6-in. 
BRUNTON-PEARCE POCKET MINING TRANSIT 
COMPASS, 3-in. dia 



19 
5 
i 



or 



500 



POCKET DIALS. 




Fig. 27. 
POCKET DIAL, with raised graduated ring, bar-needle 

and stop, 3-in. dia. 

DITTO with sights reading both ways, and cover, 3-in. dia. 
DITTO 4-in. dia. 

DITTO 5-in. dia. 

Sling leather cases for above, 4/6, 5/6, and 6/6 each. 
Light mahogany tripod stand with ball and socket joint 

fitted to either of above 

CLINOMETER COMPASSES. 



i 5 

I 10 





Fig. 28. Fig. 29. 

186. CLINOMETER COMPASS, which may be used as a pocket dial 

; with sights, or as a level or clinometer, reading the dip in degrees or 
inches per yard. In case complete, 3-in. diameter ... i is. od. 

187. DITTO 4-in. diameter i 55. od. 



LONDON, YORK AND CAPE TOWN. 



26 



T. COOKE & SONS, LIMITED, 



CLINOMETERS. 




Fig. 30. 




Fig. 31. 



De Lisle s Clinometer. 



No. 

189. DE LISLE S CLINOMETER, for the tracing of roads, 

etc., marked for levels and gradients up to i in 50, fitted 
in leather case with shoulder strap 

190. ROAD-TRACER, Ceylon pattern, marked rising and falling 

gradients, with supporting staff and target 

191. WATKIN S SERVICE PATTERN CLINOMETER, in case 

192. RULE PATTERN CLINOMETER, 6 in. boxwood, with 

flush vernier arc, large swing compass, bar needle, 
and useful tables marked on side, in case ... 

193. DITTO cheaper pattern 

194. CLINOMETER, gun-metal, with divided arc, two spirit 

levels, 2-in. compass, folding sights, etc., in case, com 
plete. Tripod stand with ball-and-socket joint 

195. DITTO in aluminium ... 

196. PLATELAYER S LEVEL, i2-in., adjustable, giving 
gradients, in case 



5. d. 



400 

2 IO O 



250 

i 15 o 

500 
5 15 o 

I 10 O 



LONDON, YORK AND CAPE TOWN. 



T. COOKE SONS, LIMITED, 



27 



Clinometers. 




Fig. 32. 

197. OPTICAL SQUARE, with adjustment, in solid leather 

case, with shoulder strap 

198. DITTO double, reflecting 90 simultaneously to both hands, 

with adjustment, in solid leather case 




Fig. 33. 
200. OPTICAL SQUARE round pattern, in case 




Fig. 34. 

202. ABNEY S LEVEL or Clinometer, 5-in. in case 

203. DITTO 7-in. with considerably larger arc. ... 

204. DITTO 4-in. with fine adjustment by tangent screw, in 



morocco case 




Fig. 35. 
205. POCKET REFLECTING LEVEL, with prism, in case 



i 8 o 
2150 



i i 



200 

2 15 O 

3 10 o 



0180 



LONDON, YORK AND CAPE TOWN. 



28 



T. COOKE & SONS, LIMITED, 




Fig. 36. 

206. CROSS-STAFF-HEAD, Octagonal, for setting out angles 

of 45 or 90, with compass, packed in a wooden box ... 

207. DITTO without compass, as illustrated 

208. DITTO Cylindrical, with divided circle and screw adjust 

ment, for setting off any angle, with compass 

209. DITTO without compass 

210. DITTO open, pattern for right angles only, without com 

pass, in case ... 

211. LIGHT TRIPOD STAND for any cross staff head 

212. PLAIN STAFF, iron shod, for ditto 



o 17 o 

10 6 

200 

1 15 o 



O 12 
O IO 



PLANE TABLES. 




Fig. 37. 

213. PLANE TABLE, with board ly-in. by 14-111., in canvascase with shoulder 

straps. Boxwood alidade with folding sights and divided edges, 
trough-compass and circular spirit level. Tripod stand of framed 
pattern ... ... ... ... ... ... ... ^"4 os. od. 

214. DITTO as above, but fitted with a ball-and-socket joint for 

quick levelling ... ... ... ... ... ... 6 os. od. 

215. Telescopic Stand for either of the above, extra ... i 55. od. 

216. DITTO with board 23-in. by i6-in., having special means of rapidly 

stretching and fixing the paper, ball-and-socket levelling arrangement, 
gun-metal alidade with removable sights. Trough compass and level 
bubble. Folding tripod stand. The whole packed in a strong 
case & os. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 29 

Plane Tables. 

217. PLANE TABLE, as No. 216, but with three screw levelling arrange 

ment, gun-metal alidade with removable telescope carrying bubble, 
and removable sights at ends, suspending fork and plumb-bob. 
Aperture of telescope -875 in. and power 10. See fig. 37 11 os. od. 

218. DITTO with board 24 in. by 18 in., having slow-motion adjust 

ment in azimuth and clamp, centering arrangement, three screws for 
levelling, and special means of rapidly stretching and fixing the paper. 
Gun-metal alidade with removable telescope carrying bubble and re 
movable sights at ends. Square aluminium plate carrying 3 in. circular 
compass and cross-bubbles, suspending fork and plumb-bob. Aperture 
of telescope 1-125 m - an d power 16. Folding tripod stand. The whole 
packed in a strong case ^"13 los. od. 

219. DITTO as No. 218, but with board 26 in. by 21 in. and telescope 

of i 35-in. aperture, power 20, and stadia lines. Strong tripod stand 
of framed pattern, not adjustable or folding, and not packed in case 

16 IDS. od. 

220. Vertical Circle with slow-motion adjustment to either of the last two, 

extra 2 os. od. 

221. DITTO as No. 219, but with board 30 in. by 24 in., or to suit re 

quirements. Anallatic lens to telescope and vertical circle with slow 
motion adjustment. Aperture of telescope i 35-in. and power 25 

20 os. od. 

222. Canvas and leather-bound case to any tripod, extra i os. od. 

223. ,, ,, ,, cap to any tripod head, extra o js. 6d. 




Fig. 38. 

225. CAVALRY SKETCHING BOARD (for use on horseback), with brass 
rollers for carrying the paper, bar-needle compass, wrist-strap and 
straight-edge i 155. od. 



LONDON, YORK AND CAPE TOWN. 



30 T. COOKE & SONS, LIMITED, 



In consequence of the War Office Regulations, 
which prohibit the sale of Government Pattern Instru= 
ments without permission, we neither illustrate nor 
describe the different patterns of Rangefinders, Meko= 
meters, Heliographs, Gun=sights, etc., made by us. 
We are prepared, however, to apply for the necessary 
permission, and to quote for any of these instruments, 

on application. 

T. COOKE & SONS, LTD. 



LONDON, YOUK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



237. 
238. 
239. 



HELIOTROPES. 

HELIOTROPE, as used on the Indian Surveys, consisting of a mirror 
carried in a frame, and mounted on a tribrach, with rack motions 
for turning about both vertical and horizontal axes. Fitted in a box 
which is made to be used as a stand. 

s. d. 

With 4-in. mirror each 600 

,, 6-in. ,, ... ,, 800 

,, 9-in. ,, ,, ii o o 



PRISMATIC COMPASSES. 



No. 

241. 

242. 

243- 
244. 

245- 
246. 
247. 




Fig. 40. 

PRISMATIC COMPASS, with graduated aluminium ring, shades, and 
mirror, fitted in a solid leather case, with shoulder strap. Light 
mahogany tripod stand with ball-and-socket joint. 

s - d - 
3-in. diameter of ring, divided to i 400 

,t ,, 4 10 o 

3 500 

n 5 10 O 

,, ,, ... ... ... ... 600 

700 

If without tripod stand, 25/- less. 



4-in. 
4^-ir 
5-in. 
6-in. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Prismatic Compasses. 



No. 

249. 

250. 
251. 

252. 

253- 
254- 

255- 
2 5 6. 




Fig. 41. 

Hutchinson s Military pattern, with card dial, 2^ -in. dia. 
in leather sling case ... 

DITTO 3i-in. dia 

Major Yerner s Service Pattern, luminous, in leather 

sling case 
Barker s Combined Prismatic Compass and Altitude 

Instrument, 3-in. dia., in solid leather sling case 

DITTO smaller 

NIGHT MARCHING COMPASS, with graduated aluminium 
dial and luminous centre, in bronzed case, with sight in lid 

BARKER S NIGHT MARCHING COMPASS 

MAJOR LEIGH S LUMINOUS 




Fig. 42. 

257. SERVICE PATTERN PRISMATIC COMPASS, Mark V., 
with hinged lid, 2^-in. dia. and sighting line. In sling 
leather case 



200 

2 IO O 
2T5O 



44 

33 



i 14 



3 15 



LONDON, YORK AND CAPE TOWN. 



T. COOKE SONS, LIMITED, 



MAGNETIC COMPASSES. 





Fig. 43. 



Fig. 44. 



No. 
260. 
261. 
262. 



POCKET MAGNETIC COMPASS, in gilt or nickel case with stop, 
enamelled dial, open face, best bar needle and agate cap, in morocco 
case. 

s - * 
if-in. diameter ... ... ... o 10 o 

if-in. o ii o 

2-in. o 12 o 



DITTO with Singer s patent pearl dial and agate cap, in 
morocco case. 

263. if-in. diameter ... ... ... o 10 o 

264. if-in. ,, o ii o 

265. 2-in. ,, ... ... ... o 12 o 




Fig. 45. 
Pocket Magnetic Compass in brass case. 



LONDON, YORK AND CAPETOWN. 



34 T. COOKE SONS, LIMITED, 



Magnetic Compasses. 

POCKET MAGNETIC COMPASS, in brass case, with lid 
and stop, bar needle and agate cap. See Fig. 45. 

With card With silvered 

dial. metal dial. 

267. if-i n dia. ... ... 040 050 

268. if-in. ,, 046 056 

269. 2-in. ,, ... ... 050 060 

270. 2^-in. , 056 066 

271. 2^-in. ,, 060 073 

272. 2|-in. ,, 066 080 

273. 3-in. ,, ... ... 070 090 

274. DITTO Royal Geographical Society s pattern, 2-in. dia., 

with aluminium or pearl dial, in gun-metal and leather 

cases i i o 




Fig. 46. 

i^-in. if-in. 2-in. 

275. BRONZE HUNTER COMPASS, with bar needle i 3 /- i5/- ijj- 

276. DITTO with Singer pearl dial ... ... ... i4/- i6/- i8/- 

277. DITTO with bar needle, combined with sundial o 18 o 

278. BOAT COMPASS, in mahogany case, 3-in., g/- ; 4-in., n/-; 6-in., i5/- 

279. POCKET GIMBAL COMPASS, in leather case 120 

280. BRASS BOAT BINNACLE, 4-in., card dial 220 

281. MINER S COMPASS or Dipping Needle, 3-in., in pocket case i 5 o 



QUADRANTS. 

84. 7-in. METAL QUADRANT or HALF SEXTANT, with extended arc 
divided on silver to i5-secs. Coloured shades, prospect and blank 
telescopes, in mahogany case ... ... ... ... 5 os. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



35 



SEXTANTS. 




285. 6-in. THREE-CIRCLE FLAT LIMB METAL SEXTANT, long centre 
with cap, rising piece, arc divided on silver to io-secs., long telescope, 
prospect and blank, coloured shades, packed in mahogany case 

6 155. od. 



286. 6i-in. ditto three circle edge bar 



155. 



od. 



287. 6Hn. THREE-CIRCLE EDGE BAR BRITANNIA CADET PATTERN 

SEXTANT, superior finish, long centre with cap, rising piece, capped 
adjustment, reflector to vernier, best index and horizon glasses, neutral 
tint shades, arc divided on silver to io-secs., long telescope with extra 
power, blank, achromatic star telescope, two dark heads, and long 
handle with ivory plate for noting readings. Packed in polished 
mahogany case with flush handle, name-plate and circular fastenings. 
With Kew certificate, Class A. 11 155. od. 

288. 7i-in. TRIANGULAR PATTERN SEXTANT, long centre with cap, 

rising piece, arc divided on silver to io-sec., capped adjustment, 
reflector to vernier, coloured shades, long telescope, prospect and 
blank. In mahogany case g os. od. 



LONDON, YORK AND CAPE TOWN. 



36 T. COOKE & SONS, LIMITED, 

Sextants. 

289. 7i-in. TRIANGULAR PATTERN SEXTANT, with bridge handle, long 

centre with cap, rising piece, capped adjustment, reflector to vernier, 
arc divided on silver to io-secs., best index and horizon glasses, 
neutral tint shades, long telescopes with extra power, prospect, blank, 
and two dark heads. Packed in mahogany case with name-plate and 
flush handle IQ ios. od. 

290. 8-in. TRIANGULAR PATTERN SEXTANT, bridge handle, best make, 

with strapped adjustment, swing horizon, cup-and-bal] tangent screw, 
swing reflector to vernier, arc divided on silver to io-secs., best 
horizon and index glasses and neutral tint shades, large size long 
telescopes, with extra power, prospect, blank, and two dark heads. 
Packed in a mahogany case w r ith name-plate and flush handle 

^"14 os. od. 

291. Extra for neutral tint shades when not included ... o 153. od. 

292. Extra for best index and horizon glasses and neutral tint shades when 

not included ... ... ... ... ... ... i os. od. 

294. Kew Certificate, Class A, to any sextant, if not included in 

price quoted ... ... ... ... ... ... ... o 15 o 



Sextant and Quadrant Accessories. 

296. BINOCULAR TELESCOPE for use with sextant, best quality conical 

bodies, oxidised or bright brass mounts with milled edge flange for 
clamping to the rising piece ... ... ... ... i os. od. 

s. d. 

297. Long Telescope, ordinary size ... ... ... each on 6 

Ditto large ... ... ... ... ... ,, o 14 6 

Ditto with outside cell ... ... ... ,, o 16 6 

298. Short or Prospect Telescopes, ordinary size ... ,, 046 

Ditto large ,, 060 

Ditto with outside cell ... 080 

299. Blanks, ordinary size ... ... ... ... ... ,, 020 

Ditto large ,, 036 

300. Star Telescopes, small ... ... ... ... ,, 090 

Ditto large ,, o 14 o 

Ditto with outside cell ... ... ... ,, 0180 

301 . Solid leather case to any sextant, strongly made, best 

quality ... ... ... ... ... ... ,, i i o 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



37 



BOX SEXTANTS. 



No. 




Fig. 48. 



305. BOX SEXTANT, 3-111. diameter, divided on silver, with 

telescope, shades, etc., fitted in a solid leather case, with 
shoulder-strap 

306. DITTO with supplementary arc ... 

307. Light mahogany tripod stand, with ball and socket joint, 

fitted to either of above 



* * 

440 
550 



ARTIFICIAL HORIZONS. 




Fig. 49. 

308. ARTIFICIAL HORIZON, plane black glass, rectangular or circular, 

with three levelling screws and spirit level, in mahogany case 

2 55. od. 

309. DITTO best mercurial, with roof, trough, and turned iron bottle, filled 

with mercury, in a mahogany case ... ... ... <{ los. od. 

310. DITTO of cheaper make ^3 IDS. od. 

311. DITTO Captain George s pattern, in cast iron, having two chambers 

with connecting valve, the mercury being stored in one and allowed 
to run into the other when required for use ; plane glass surface and 
levelling screws ... ... ... ... ... ... \ 153. od. 

312. DITTO in aluminium ... ... ... ... ... 6 os. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



SHIP-LOGS. 




No. 



318. 



320. 

321. 
322. 
323. 



Fig. 50. 



314. WALKER S PATENT Al. "HARPOON" SHIP-LOG 

315. DITTO A2. 



* 

2 17 
2 10 




Fig. 51. 

WALKER S PATENT "CHERUB" SHIP-LOG, with regis 
tering apparatus for fixing to taffrail, and two rotators ... 4 10 

WALKER S PATENT "CHERUBAL" SHIP-LOG, with ball 
bearings, similar in outward appearance to the Cherub 
but with sliding case through which the wheels can be 
readily oiled . . 4 18 

Extra rotators, for Cherub or Cherubal Ship-logs ... o 19 

Brass Fly- Wheel Governor, for use with Cherub, Cherubal 
and other ship-logs ... ... ... . . ... ... o n 

Ship-log Swivel o 10 

Best Quality Log Lines, 40 fathoms, No. 8, I2/-; No. 10 o 15 
Ditto 50 ,, ,, i5/- o 19 

WALKER S " HARPOON " SOUNDING MACHINE, a 
thoroughly reliable mechanical sounder ... ... ... 2 10 




Fig. 52. 

325. WALKER S PATENT "EXCELSIOR" YACHT-LOG, com 

plete with register, rotator, 100 feet of line and sinker. 
Packed in a box 

326. Extra rotators for do 



360 
o 10 o 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



LEVELLING STAVES, ETC. 



s 





J- 




47 




5 

-=. 




4v 




pi 




43 




7 




1 




ijv 




47 




J3 




4v 

._7S^U 


X" ~VX - *f "** ~ ~ "^- 

Fig. 55. Fig. 56. 
Hundredths. Fiftieths 



Fig. 53. Fig. 54. 

Half-Centimetres. Fiftieths. 

SOPWITH S TELESCOPIC LEVELLING STAFF, of best construction, 
strong mahogany, brass bound, with painted readings, Cooke s pattern 
(Fig. 55) and several others, in feet and metres. 

No. 

329. In two lengths, 12 feet long, closing to 6-ft. 8-in., inner and 

middle ... 

330. DITTO outer and middle 

331. In three lengths, 14 feet long, closing to 5-ft. 3-in 

332. DITTO 1 6 feet long ,, 6-ft. 3-in 

333. DITTO 5 metres long ,, 2 metres 

334. DITTO 18 feet long ,, y-ft. 3-in.... 

335. DITTO 9 feet long, closing to 3-ft. 6-in., for underground 

use ... ... ... ... ... ... ... 20 

336. ROLL-UP RUBBER BAND, stencilled any standard 

pattern, for use as a portable staff, lo-ft. long ... ... 012 



1 IO 

I 15 

2 5 

2 12 

2 12 

3 3 




Fig. 57. 

337- FOLDING STAFF OR STADIA ROD, with strong hinge, 

12 feet long, closing to 6 feet ... ... ... 2100 

338. DITTO 14 ,, 7 2 15 o 

339. DITTO 16 ,, 8 300 

Stadia Rods can be graduated to read i in 50, i in 100, or any other 

ratio desired. The illustration shows a rod graduated to -,Vt-hs of a foot and 
reading i in 100. 

Staves or Stadia Rods painted to Engineers own designs at an extra cost. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Levelling Staves, etc. 



No. 
34- 



34*- 
342. 
343- 
344- 
345- 

346. 



347- 





Fig. 59. 

PORTABLE CIRCULAR BUBBLE for fixing to the back 
of staff or stadia rod, and folding up flat when not in use 

CANVAS CASES, Leather bound- 

For one 14 feet staff 

For one 12 feet, 16 feet or 5 metre staft 

For one 18 feet staft or 12 feet folding stadia rod ... 

For one 14 feet folding stadia rod 

For one 16 feet do. 



STAFF PAPERS, for re-papering staves, of any regular 
pattern, 12 feet, 2/6; 14 feet, 3/- ; 16 feet, 3/6 ; 18 feet ... 

LEVELLING STAFF PROTECTORS, for attaching a 
tripod stand to the face of the staff for convenience in 
carrying, at the same time protecting the latter. In two 
patterns for solid round, or framed pattern tripods 

per pair 



* d. 

O 12 6 

o 15 o 
o 16 6 
0180 



o o 

2 O 



3 6 



SURVEYORS 



RODS, ETC. 

RANGING POLES, painted two or three colours, and iron shod 
348. 6 feet long, divided feet ......... per doz. 

349 7 n 

350. 8 

351. 10 

352. 12 



10 
15 



i 
i 

2 O 

2 15 

3 10 



BAMBOO RANGING POLES, with brass ferrule at top and iron shod 



353- 
354- 
355- 
356. 



357- 

358. 



6 feet long 
7 



10 



Brass jointing, 24/- per doz. extra. 

OFFSET ROD, 10 links, shod, with point 

BONINGIRODS, per set of three 



each 



1 16 

2 2 
2 8 
2 15 

O 3 

o 15 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Surveyors Rods, etc. 




Straight. 
5. d. 



Folding. 
5. d. 



No. 

359. SURVEYORS RODS, ash, natural wood, painted 

feet and quarters, 5 feet long, per pair 5 6 

360. DITTO lancewood, fully divided and engraved, 

natural wood or stained black, 5 feet, per pair ... 80 10 o 

361. DITTO 6 feet, per pair 10 o 12 o 

362. SOLID LEATHER CASE to hold a pair of 5 feet 

folding rods 76 

363. DITTO to hold a pair of 6 feet folding rods ... 9 o 

364. FLAGS for Surveying Poles, white and red y/-, g/- & i2/- per doz. 

366. SURVEYORS WALKING STICK, with 5 ft. rod, malacca 

cane 150 

367. DITTO crooked bamboo cane ... ... ... ... 150 

368. DITTO silver-mounted root bamboo ... ... ... 0160 

369. DITTO plain ,, ,, o 13 o 

370. TROPICAL UMBRELLA, large size, double, with jointed 

stick and spike i 12 o 

371. DITTO smaller, without stick and spike ... ... ... o 12 6 



373. RECESS RODS 

small, 5/- ; large, 6/6 

374 HORSE STANDARDS 

20/-, 2 5 /-, 3 0/- 

375. DITTO portable, in walking stick, 
as illustrated ... ijj- to 3O/- 



Fig. 63. 




LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



LAND SURVEYING CHAINS. 




Fig. 64. 
4 Pole Surveying Chain. 

The four pole chains are divided into links and tallied at every ten links ; 
the 50 and 100 feet chains are divided into feet and tallied at every ten feet ; 
the metre chains are divided into fifths of a metre and tallied at every two 
metres. 



No. 


DESCRIPTION. 


LENGTH. 




50 Feet. 


4 Poles. 


ioo Feet. 




Made of best iron wire, with three oval 
rings, brass swivel handles and tallies. 










381 


No. 8 W. G 


5/6 


71- 


8/- 


Each 




Made of best cast steel wire, with three 
oval rings, brass swivel handles and 
tallies. 










382 


No. 8 W. G 


!0/- 


5/- 


i8/- 


jj 


383 


,, 10 ,, 


8/6 


13/6 


i6/- 


j? 




,, 12 


7/6 


12 1- Hl- 


j j 


384 


,, 12 ,, all joints brazed ... 


/- 


2I/- 


*3l~ 





No. 


DESCRIPTION. 


LENGTH IN METRES. 




10 


20 


25 




Made of best iron wire with three oval 
rings, brass swivel handles and tallies. 








385 


No. 8W. G : 5/- 7/6 


9/- 


Each 




Made of best cast steel wire, with three 
oval rings, brass swivel handles, and 
tallies. 










386 


No. 8W. G 


8/6 


I5/- 


i9/- 


jj 


387 


12 


6/6 


I2/- 


5/- 


j> 



Any of the foregoing may be had galvanised, or with all joints brazed, 

so as to form a solid chain. 
Chains in all Foreign Measurements to order. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



43 



Land Surveying: Chains. 



388. LAND CHAIN STRAPS 

LAND CHAIN ARROWS. 

15 INCHES LONG, IN SETS OF TEN. 
Made of best cast steel wire. 



389. No. 8 W. G. 



390. 



10 



Made of best iron wire. 

391. No. 7 W. G. 

392. ,, Galvanised 

393. LEATHER QUIVER for Arrows 



s. d. 

o 6 each. 



s. d. 

i 6 per set. 

i 3 

i o 

i 3 

i 6 each. 



COMPOUND STEEL-BAND CHAINS. 

These are usually employed in two or more separate lengths, made 
attachable by swivels and hooks. The first length of each set is divided 
in the usual manner into links or feet and numbered at every ten, the 
others not being subdivided. 

Each set is provided with handles and wound upon a steel cross, which 
is included in the prices quoted below, but a metal reel may be had if desired, 
at an extra cost. 







LENGTH IN CHAINS OF 100 LINKS. 




No. 


WIDTH OF BAND. 
















2 


3 


4 


5 




397 


-in. Steel Band 


i6/- 


20/- 


25/- 


30/- 


Each 


39& 


i-in. ,, 


i6/- 


20/- 


2 4 /- 


28/- 


>i 


399 


-rV in - 


"/- 


i5/- 


1 8/6 


22/- 


jt 



Single Four-pole lengths for repairing the above, without handles : 

400. The first four-pole length, sub-divided, ^-in., 8/- ; |-in.,9/-; T yin., 7/- 

401. The other lengths, not sub-divided, -in., 4/6; |-in., 4/-; T V-in., 3/- 





LENGTH IN FEET. 




No. i WIDTH OF BAND. 


_ 





. 









200 


300 


400 


500 




402 i-in. Steel Band 


20/- 


2 7 /- 


34/- 


4 2/- 


Each 


403 i-in. ,, ,, 


i8/- 


2 4 /- 


3 o/- 


3 6/- 





404 T yin. 

i 


5/- 


I8/- 


22/- 


28/- 


> 



Single 100-ft. lengths for repairing the above, without handles : 

405. The first loo-ft. length, sub-divided, 

i-in., io/-; i-in., 10/6; ^-in., 7/6 
The other lengths, not sub-divided, 

i-in., 6/3; i-in., 5/6; T yin., 3/6 

406. METAL REEL for any of the above, 7/6 

Long lengths in one piece, of any width required, can be supplied to 
order. 

407. Repairing Outfit consisting of hand punch, 2-doz. brass sleeves, i gross 

rivets, and i spare punch, in box, io/-. 



LONDON, YORK AND CAPE TOWN. 



44 



T. COOKE & SONS, LIMITED, 



STEEL-BAND MEASURING CHAINS. 





4 Poles on Cross. 

Fig. 65. 



4 Poles in Case. 

Fig. 66. 



A standard measure, practically unalterable ; strong as a chain, but 
much lighter and more compact. When not in use it is coiled on a steel 
cross, which is included in the prices quoted below, but it can be fitted 
with a metal case at an extra cost. 



No. 


FEET AND LINKS. 


Width 
of 
Band. 


50 


66 

100 


IOO 


Feet. 
Links. 


411 


Divided into links and numbered 


f-in. 




13/6 




Each 


412 


" 


~H )) 




i8/- 






at every 10 links. 


f 




20/- 




J 

J) 


414 , 


9. Ji 


0/6 


i6/- 




Divided into feet and numbered 1 






" 


45 1 * " 
/- at every 10 feet. 

4 \ I JL ft 


is/" 




22/- 
26/- 


>J 
) J 


4 1 ? 


/ \ M 


JO/ 


l6/- 22/- 




418 


Etched feet one side and links 5 R , 


2 3/- 32/- 




419 


the other. 


1 H 


20/- 


2 5/- 37/- 


,, 


420 

421 


Etched feet, inches, and eighths 




-/ 


2 1/- 3 0/- 

26/- 38/-- 


JJ 


422 


one side and links the other. 
I 


t 


2 4 /- 




44/- 





LONDON, YORK AND CAPE TOWN. 



T. COOKE SONS, LIMITED, 



45 



Steel Bands. 



No. 


FEET AND METRES. 


Width 
of 
Band. 


50 
15 


66 

20 


25 


100 

30 


Feet. 
Metres 


426 




J-in. 


i 4 /- 


IJ/- 


2I/- 


2 4 /- 


Each 


427 


Etched feet one side and 


fi M 


i 9 /- 


2+1- 


30/- 




428 


decimetres the other. 


3 

4 >) 


20/6 26/- 


32/- 


^8/~ 


429 


Etched feet, inches, and f 


i 


20/- 


25A 


30/- 


3o/" 5, 


430 


eighths one side, and^ 


5. 

8 J> 


25/- 


3 2 /- 


39/- 


4 6 /- 


43 1 


millimetres the other. [ 


f 


28/- 


3 6/- 


44/ 


53A 


M 




METRES. 














432 


Divided into fifths of a 


* 




13/6 




ig/- 


,, 


433 


metre and numbered at- 


1 , 




i8/- 




2 5/- 





434 


every second metre. 


t M 




20/- 




28/- 


435 




1 ,, 


H/- 


iy/- 


2I/- 


2 4/- 


436 


Etched decimetres both 


f ,. 


i 9 /- 


24/- 


3/- 


3 6 /- > 




* j 












437 


SlQCo. 


f 


20/6 


26/- 


3 2/- 


3/- 


438 




i 


20/- 


2 5/- 


3 0/- 


3 6/- 














1 




439 




g 


25/" 


32/~ 


39/- 


4w~ " 
















440 




1 ,, 


28/- 


36/- 


44/ 


53/- 



No. 


CAPE FEET. 


Width 
of 
Band. 


eo 


66 




IOO 


Cape 
Feet. 


443 


Etched feet, tenths, and ( 


i-in. 


22/- 


24/- 




34/- 


Each 


444 


hundredths, on one sidej 


f 


a?/- 


3 o/- 




43/- 





445 


only. \ 


3. 

4 > 


3i/- 


34/- 




5/- 





446 


Divided into feet and 


i 


20/- 






2 4 /- 


M 


447 


tenths, and numbered at- 


1 , 


26/- 






38/- 


)i 


448 


every ten feet. 


f 


28/- 






4 2/- 


>) 



449. METAL CASE (in place of cross) for J-in. or -|-in. band, 4/- 

450. DITTO for f-in. or f-in. band, 6/- 

Other lengths may be obtained, and any of the above may be had f-in, 
wide, if required, at proportionate cost. 

451. Metal Crosses for bands, 3/- 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



WIND-UP MEASURES OF BEST MAKE. 




Fig. 67. 
With Steel Tapes. 

Steel Tapes are usually marked feet, inches and eighths on one side and 
links on the other, and this pattern will always be supplied unless special 
instructions are received that they are required otherwise. They may be had 
marked in a variety of ways, as below : 





g In leather case with 


Tape only, without 






^ 


<j5 flush handle. 


case. 




No. 


DESCRIPTION. +; 


JB 




















JT 


^ 15 


20 





30 


15 


20 





30 


Metres 






50 


66 


75 


100 


50 


66 


75 


100 


Feet 


455 


Marked London and 12ths ; 


-in. 15/- I 19/- 


21/- 


26/- 


10/6 


14/- 


16/- 


21/- 


each 




(feet into inches and 8ths) 


















456 


or London and lOths (feet J 


-in. 19/- ! 24 /- 


26J- 


33/- 


14/- 


18/- 


20- 


27/- 






into lOOths), on one side 


















457 


only. jj 


-in. 231- 


29/6 


32/6 


42, - 


17/6 


23/- 


261- 


35/- 


" 


458 


Marked as above on one f 


-in. 17/6 


22f- 


25/- 


31/- 


IS/- 


17/- 


201- 


26/- 






side, with links on back, 




















459 


or marked metres, c/ms and 


-in. 21/- 


271- 30f- 


38/- 


16/- 


21/- 


24,1- 


321- 






m/ms on one side only. 


















460 


1 


-in. 24/6 


31/6 


34/6 


45/- 


19/- 


25/- 


28/- 


381- 





461 


f-in. 21/- 


27/- 


29/6 


38/- 


16/6 


221- 


24/6 


33J- 


. 


462 


Marked with any 2 meas 
urements, one on each side. 2 


-in. 25/- 


33 - 


36/- 


46/- 


20/- 


271- 


30/- 


W 





463 


1 


-in. 29/6 


38/6 


42/6 


55/- 


2,1- 


321- 


36/- 


48/- 






Any of the above can be had ^-in. or f-in. wide at proportionate prices, 

and any other length can be supplied to order. 
Steel Tapes are made in all Foreign Measurements and charged 

according to their equivalent in English. 

Steel Tapes in German Silver Cases. 

Convenient for the Pocket. 



Marked one or both sides with any one or two measurements : 

I2-ft. l8-ft. 



466. 



With -^-in. tape 



7/6 



10/6 



25-ft. 

IS/ 



LONDON, YORK AND CAPE TOWN. 



T. COOKE SONS, LIMITED, 



47 



WIND-UP MEASURES OF BEST MAKE. 





Fig. 68. 



Fig. 69. 



The folding handle is the cheapest, most serviceable, and the easiest 
to wind, but the flush handle has the advantage of lying flat to the case, 
and so taking up less space in the pocket. 

Chesterman s "Constantia" and Rabone s " Rigida" Tapes are recom 
mended for accuracy and durability. Metallic (wired) tapes can be supplied 
at the same prices. 

In one width only, f-inch. 







Marked on both sides. 






Constantia} 












No. 


Rigida > Tape |-in. wide. 


15 


20 


25 


30 


Metres 




Metallic ) 


















50 


66 


75 




100 


Feet 


4 6g 


In Leather Case with 
















Folding Handle 


6/6 


7/6 


8/3 


9/- 


10/6 


each 


470 


In Leather Case with 
















Flush Handle 


7/- 


8/3 


9/- 


9/9 


1 1/6 


> > 


47i 


Tape only, without case... 3/9 


4/6 


5/- 


5/6 


7/3 


> > 



WITH LINEN TAPES. 



In one width only, 



No. 


Linen Tape J-in. wide. 


Marked on both sides. 


Metres 
Links 
Feet 


10 

50 
33 


15 
50 


20 
IOO 

66 


75 


25 


472 


In Leather Case with 
Folding Handle 


3/6 


4/6 


5/- 


5/6 


6/- 


each 


473 


In Leather Case with 
Flush Handle 


4/- 


5/- 


5/9 


6/3 


6/9 


5) 


474 


Tape only, without case... 


1/6 


2/- 


2/9 


3/- 


3/6 


> J 



LONDON, YOKK AND CAPE TOWN. 



4 8 



T. COOKE SONS, LIMITED, 



No. 

478. 



479- 

480. 
481. 
482. 

483- 

484. 



486. 

487. 
488. 
489. 
490. 

491. 
492. 

493- 



ANEROID BAROMETERS. 





Fig. 70. 



Fig. 71. 



WATCH SIZE ANEROID, if-in. dia., gilt or nickel case, 
silvered-metal dial, with revolving altitude scale to 8,000 
feet, in snap morocco case ... 

DITTO better quality movement 

If compensated for temperature ... ... ... extra 

DITTO best quality, 5,000 feet to 10,000 feet, compensated 

DITTO in hunter case ... 

DITTO as No. 481, with raised dial and thermometer 

DITTO but with small Singer pearl compass and thermo 
meter on reverse 

DITTO but with full size bar needle, or Singer pearl com 
pass on reverse 

Keyless action to any of the last five 

DITTO as No. 481, but in hall marked silver case 

DITTO in silver hunter case 

Keyless action to either of the last two 

DITTO as No. 487, but with keyless action and small 
Singer pearl compass and thermometer on reverse 

DITTO but with full size bar needle or Singer pearl com 
pass on reverse 

DITTO as No. 481, but with keyless action, in g-ct. gold 
case and outer morocco case ... ... i$-in. dia. 

if-in. dia. 

DITTO in i5-ct. gold case ... ... ... i-J-in. dia. 

if-in. dia. 



* <*. 



I O 

IO O 

3 o 

8 o 

13 o 

16 o 



3 12 o 



9 
10 

ii 
13 



12 O 

7 
17 o 

I 5 o 

12 O 

8 o 



o o 

o o 

o o 

o o 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



49 



Aneroid Barometers. 



No. 
496. 



497- 

498. 
499. 
500. 

501. 





Fig. 72. 



Fig. 73. 



POCKET SIZE ANEROID, 2^-in. dia., gilt or nickel case, 
silvered metal dial, compensated, with weather range only, 
curved thermometer, in snap morocco case 

DITTO Watch form, Geographical Society s pattern, with 
revolving altitude scale, 5,000 feet to 10,000 feet 

DITTO with raised dial and thermometer ... 
Keyless action to either of the last two ... 

Full size bar needle or Singer pearl compass on reverse 

of any of the above 
Leather sling case in lieu of morocco 




2 12 O 

2 12 O 
3OO 
080 

i 6 o 
060 



Fig. 74. 
Military-Engineering;, and Surveying Aneroid. 



LONDON, YORK AND CAPE TOWN, 



50 T. COOKE SONS, LIMITED, 

Aneroid Barometers. 

BEST QUALITY CYLINDRICAL ANEROID, in bright brass or bronzed 

metal case, compensated, silvered-metal dial with fixed or revolving 

altitude scale, 5,000 feet to 10,000 feet, in morocco case: 

55- 3-in. dia. ... 3 12 o 

506. 4-in. dia. ... 3 16 o 

57- 5- in - dia. ... 400 

508. DITTO with raised dial and thermometer, 3-in. dia. ... 3 18 o 

59 4-in. dia. ... 420 

510- 5-in. dia. ... 460 

511. Magnifying Lens to any of the above 076 

512. Aluminium case in lieu of brass or bronze : 

3-in., i6/- 4-in., 2o/- 5-in., 24/- 

513. Leather sling case, in lieu of morocco : 

3-in., 6/- 4-in., 7/6 5-in., g/- 

All the above Aneroids are priced with altitude scales 5,000 feet to 
10,000 feet, except where otherwise stated. Above 10,000 feet, every 
5,000 feet will be charged 7/6 extra, and below 5,000 feet every 1,000 feet will 
be charged 5/- extra. 




No. Fig. 75. 

515. SPECIAL SURVEYING or MINING ANEROID, in stout bronzed 

metal case, 5-in. dia., with silvered metal dial. Fixed altitude scale, 
graduated to 20 feet and reading by a vernier to single feet. Circle 
divided as desired, 5,000 feet to 10,000 feet ascent, or 4,000 feet ascent 
and 2,000 feet descent. Rackwork adjustment to vernier and rotating 
magnifier. In leather sling case ... ... ... ^"7 los. od. 

Altitude scale above 10,000 feet ascent, io/- extra for every 5,000 feet. 

Altitude scale below 5,000 feet ascent, 5/- extra for every 1,000 feet. 

516. Aluminium case to above, in lieu of bronzed metal case, 3O/- extra. 

517. WATKIN S PATENT MOUNTAIN ANEROID, which can be kept out 

of gear when not in use and is only put into action when a reading is 
required to be taken, thus ensuring greater accuracy. Made in two 
sizes, 3-in. and 4^-in. dia., in aluminium case with sling leather outer 
case ... ... ... ... ... ... either size 6 6s. od. 

518. Kew Certificate to any Aneroid io/ and upwards, according to size. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Aneroid Barometers. 




521 



Fig. 76. 

STANDARD ANEROID BAROMETER, in heavy bronzed metal case, 
8-in. dia., silvered-metal dial, hand engraved, scale range 28-in. to 
3i-in., or otherwise as desired, reading by a vernier to y^^-in., com 
pensated for temperature, certificate of comparison throughout the 
scale with a verified Kew standard accompanies each instrument. 
The mechanical movement is the most perfect obtainable, and is much 
more sensitive than a mercurial barometer, showing instantly the most 
minute variation of the atmospheric pressure ... 14 os. od. 

This instrument is especially suitable for the Colonies and abroad owing 

to the difficulty of transporting standard mercurial barometers to out-of-the 

way places. 

TRAVELLING ANEROIDS, ETC. 




Fig. 77. 

523. LIVINGSTONE SET, comprising best-quality watch-size aneroid with 

full-size compass to match, and thermometer in centre, in best 
morocco case ... ... ... ... ... ... ^"4 25. od. 

524. DITTO of cheaper quality and without thermometer ... 2 I2S. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Travelling: Aneroids etc. 

525. DOUBLE-OPENING CASE, comprising best quality watch-size aneroid 

in morocco case, with small Singer pearl compass and thermometer in 
lid $ 1 8s. od. 

526. WATCH-FORM ANEROID, 2|-in. dia., in nickel case with enamel dial, 

in morocco case, to stand or hang ... ... ... i gs. od. 




Fig. 79. 



Fig. 80. 



Fig. 



529. STANDARD MERCURIAL BAROMETER, on 

Fortin s principle, bore o*5-in.; dia., with 
thermometer, opal glass reflectors and adjust 
ing screws at base. Mounted on a mahogany 
board, with Kew certificate. 11 os. od. 

530. DITTO as above, but o 3-in. bore and without 

Kew certificate 7 los. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



53 



Mercurial Barometers. 

531. GLASS CASE for Nos. 529 and 530, extra 2 5*. od. 

532. DITTO best quality, ebonised mahogany, plate glass .. \ os. od. 

533. STANDARD MERCURIAL BAROMETER, student s pattern, bore 

o-25-in., without thermometer 3 los. od. 

Other sizes and descriptions to order. 

534. MARINE MERCURIAL BAROMETER, Board of Trade pattern, 

bronzed metal frame, with thermometer. Fig. 79 ... \ los. od. 

535. DITTO round or square top frame, with one or two verniers and 

thermometer 2 45. od. to 2 los. od. 

536. DITTO with Sympiesometer ... ... 3 175. od. to 5 os. od. 

537. PEDIMENT MERCURIAL BAROMETER, in oak frame, with thermo 

meter. Fig. 80 3 os. od. to b os. od. 

538. DITTO in carved oak frame ... ... 6 os. od. to 10 os. od. 

HALL BAROMETERS. 





Fig. 81. 



Fig. 82. 



LONDON, YORK AND CAPE TOWN. 



54 



T. COOKE & SONS, LIMITED, 



Barometers. 



No. 



5-n. 



6-in. 8-in. 



24/- 28/- 33/- 
33/- 37/- 43/- 
4% 44/- 5/- 



541- CARYED OAK FRAME PENDANT BAROMETER, 

with closed porcelain dial and thermometer, in a 
number of patterns ... 

542. DITTO of better quality and finish 

543. DITTO with open face, visible works 

544. DITTO with silvered-metal dial and thermometer 

scale, best engraved 42/- 5o/- 6o/- 

545. DITTO in massive carved oak frame 48/- 66/- go/ 

and upwards. 

546. INLAID SOLID MAHOGANY Do. 47/. $8 . y^/. 

and upwards. 





Fig. 83. 



Fig. 84. 



5-in. 6-in. 8-in. 

547. CARYED OAK ROUND FRAME ANEROID, with 

closed porcelain dial ... ... ... ... i^j- ij/- 22/- 

548. DITTO of better quality and finish... ... ... 22/- 2J/- $2/- 

549. DITTO with open face, visible works 28/- $$/- $8/- 

550. DITTO with silvered-metal dial, best engraved ... 3o/- 38/- q.6/- 



LONDON, YOEK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



55 



Barometers. 




Fig. 85. 

553. DITTO in massive carved oak frame, with best-quality movement, com 

pensated for temperature, and thermometer. 

5-in., 42/- to 55/-; 6-in., 5o/- to 62/-; 8-in., 58/- to yo/- 

554. STAND FRAME CARVED OAK ANEROID, with porcelain dial. 

23/- to H/- 

555. DITTO with silvered-metal dial, best engraved 3O/- to Go/ 

Hall Barometers of Cheaper Make. 

556. Carved and polished brown or black wood, round frame, open enamel 

dial, in several patterns ... ... ... 3f-in., io/- 5-in, I7/- 

557. Carved and polished brown or black wood, pendant pattern frame, 

open enamel dial, with opal scale thermometer, in several patterns 

3f-in., i7/- 4 f-in., 22/- 

558. BRASS CASE ANEROID, with closed porcelain dial, in morocco case 

5-in., i6/- 6-in., 24/- 

559. Ditto with open porcelain or closed silvered-metal dial 

5-in., 22/- 6-in., 3o/- 

560. Ditto with open silvered-metal dial 5-in., 28/- 6-in., 36/- 

561. Curved thermometer to any of the above, 2/6 extra. 

562. Any of the above with scale reading down to 22-in. and weather words 

arranged for an altitude of 6,400 feet : 

5-in. porcelain dial ... 4/- extra. 

6-in. do. ... 5/6 ,, 

5-in. silvered-metal dial ... jj- ,, 

6-in. do. ... io/- ,, 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Barographs. 




No. 



Fig. 87. 



564. SELF-RECORDING ANEROID BAROMETER, a useful 

and reliable instrument of cheap make, in oak case with 

cover, and charts for one year 440 

565. DITTO of better quality, in ebonized case with glass shade 

cover ... ... ... ... ... ... ... ... 500 

566. DITTO with wood frame glass cover, in oak, mahogany or 

walnut. See Fig. 87... ... ... ... ... ... 600 

567. DITTO with bevelled plate-glass, and drawer with spaces 

for charts ... ... ... ... ... ... ... 700 

and upwards. 

568. DITTO but with auxiliary metal dial on which the present 

pressure is always shown ... ... ... ... ... 850 

and upwards. 

569. A special attachment with additional arm to record the temperature on 

the same drum in ink of a different colour can be fitted to any of the 
above at 4O/- extra. Special charts are desirable, price 5/6 per set. 

570. Self- Recording Aneroid for the pocket, a very handy little instrument 

for travellers, explorers and balloonists, with set of charts 7 los. od. 







(>. 88. 



571. SELF-RECORDING THERMOMETER, in hinged maho 
gany case with glass front, 20 to 100 Fahrenheit ... 600 



LONDON, YOJtlK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



57 



Thermographs. 

No. s. d. 

572. SELF-RECORDING THERMOMETER, in copper case, 

with hinged cover and handle, as Fig. 88... ... ... 6 10 o 

573. DITTO with wood frame glass cover, in oak, mahogany or 

walnut ... ... ... ... ... ... .. ... 650 

574. DITTO with extra tall clock drum, zero to 120 Fahrenheit 

or otherwise ... ... ... ... ... ... ... 6150 

575. DITTO but with bevelled plate glass and drawer, with 

spaces for charts ... ... ... ... ... ... 7150 

576. SPECIAL REFRIGERATION THERMOGRAPH, scale o 

to 70, with extra large iron base, japanned metal cover 

and large drum, with 21 days clock ... ... ... 12 o o 

All the above are supplied with bottle of ink and set of charts. 
Extra Charts for any of the above, one year s supply, 5/6 



ANEMOMETERS. 




Fig. 89. 

BIRAM S ANEMOMETER, for recording the current of air in mines, 
sewers, furnaces, etc., with disconnector, packed in a wood case. 



581. i2-in. dia., reading to 10,000,000 ft., 6 dials... 

582. 6-in. ,, ,, ,, ,, 

583. 6-in. ,, ,, 100,000 4 dials... 

584. 6-in. ,, ,, i ,000 2 dials... 

585. 4-in. ,, 



s. d. 
600 

400 
350 

2 18 O 
2 12 O 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Anemometers. 




Fig. 90. 

586. BIRAM S ANEMOMETER, 2-in. dia., reading to 1,000 ft., 

special watch form, with disconnector, two dials ... 440 

587. DAYIS S PATENT SELF-TIMING ANEMOMETER, dis 

penses with the use of a watch, in leather case 500 




Fig. 94. 

588. ROBINSON S ANEMOMETER, with 3 -in. cups, reading to 

500 miles, zero setting ... ... ... ... ... 4 16 o 

589. ROBINSON S RECORDING ANEMOMETER, in japanned 

metal case, range of chart 25 miles, recording 8 days, 
enamelled dial registering 500 miles, outer circle divided 
to 5 miles and sub-divided to T ^-ths, zero setting ... 21 o o 

Kew pattern recording anemometers of large size to order. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE SONS, LIMITED, 



59 



590. 



593- 
594- 



595- 
59 6 - 

597- 
598. 




Fig. 91. 

PORTABLE AIR METER, reading to 10,000,000 feet, with 
disconnector, 6 dials 

591. DITTO to 10,000 feet, 4 dials 

592. DITTO to 1,000 feet, 2 dials 




CURRENT METER, for use in reservoirs, rivers, or streams, 
to show the rate of flow of the current or tide 

TROCHEAMETER, for registering the number of revolu 
tions of carriage wheels, etc., in copper case with leather 
strap 

DITTO of cheaper make 

DITTO of best make, with three wheels, reading to 50,000 
revolutions 

MILOMETER, or mileage recorder, suitable for motor cars 
and other vehicles, to 10,000 miles, in brass case 

PERAMBULATOR, with wheel 26-in. diameter, for measur 
ing roads, paths, etc., and showing miles, loths and looths 



330 
300 

2 15 O 



6OO 

3 15 o 
250 

5 10 o 
3 15 o 
8 10 o 



LONDON, YORK AND CAPE TOWN. 



6o 



T. COOKE SONS, LIMITED, 



Pedometers. 




Fig. 93. 

No / 5 . d. 

599. PEDOMETER, watch size, adjustable to any length of step, 

in nickel case, up to 12 miles ... ... ... ... o n o 

600. DITTO up to 120 miles ... ... ... ... ... 0160 

601. PACEOMETER, in nickel case, to 10,000 paces i i o 

605. GAS LEAK INDICATOR, a highly sensitive instrument for 

instantly detecting the presence of gas ... ... ... 3 15 o 

606. POCKET GAS PRESSURE GUAGE, in morocco case ... 220 

607. PORTABLE RECORDING Ditto clock driven; drum 

revolves once in 24 hours ... .. ... ... ... 7120 

608. Extra charts for use with above, per 100 ... ... ... 076 





Fig. 95. 



Fig. 96. 



609. RICHARDS STEAM INDICATOR, improved pattern, in 

teak case with one spring and scale ; suitable for speeds 

up to 150 revolutions per minute ... ... ... ... 700 

610. M INNES Ditto suitable for speeds up to 250 revolutions 

per minute. Fig. 96 ... ... ... ... ... 6 10 o 

611. Each extra spring and scale for either of above ... ... o 10 o 

612. Drum Springs .. ... ... ... ... ... ... 020 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 61 



SUPERFINE METALLIC PAPER. 

613. Size 74" x 33", f or Richards Indicators, 

Packet of 240 sheets, 3/6 ; 360 sheets, 4/6 

614. Size 6\" x 3", for M Innes Indicators, Packet of 240 sheets, 3/6 

615. Best Italian Hemp Cord, large hank, 1/6 

616. Wire Core Cord, 25-ft. hank, 2/3 

SPRING BALANCES. 

SPRING BALANCES, Messrs. Geo. Salter & Co. s manufacture, for the 
use of Engineers, Surveyors, Sportsmen, Explorers, Prospectors and others, 
in a number of sizes and patterns : 

No. s . d. 

617. Improved spring, best quality, No. i, with hook: 

80 Ibs. x i lb. ... ... ... ... ... 090 

30 Ibs. x i lb. 036 

20 Ibs. x lib 050 

618. Patent No. la, strong and sensitive, with hook. These are 

plugged ready for stamping and are suitable for trade 

purposes: 

20 Ibs. x 2 ozs. ... ... ... ... ... 076 

60 Ibs. x lib 0180 

619. Small Brass Sportsman s, No. 15, with hook : 

30 Ibs. x i lb 036 

50 Ibs. x ^ lb 060 

620. German Silver ditto, No. 17, with hook: 

10 Ibs. x lib 030 

20 Ibs. x i lb 036 

621. Railway Parcels Balance: 

56 Ibs. x 2 ozs., with 7f-in. enamelled dial ... i 40 



LONDON, YORK AND CAPE TOWN. 



62 T. COOKE SONS, LIMITED, 



MAGNETOMETERS. 



VIBRATION MAGNET 



DEFLECTED MAGNET. 




Fig. 97. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Magnetometers. 

The design of the Unifilar Magnetometer, as made by us, is based on 
that of the ordinary Kevv instruments, but modified and improved in several 
important details. The above instrument has been accepted by the India 
Office as their standard pattern. 

The instrument generally consists of a graduated horizontal circle 
supported on three levelling foot-screws. Fixed to the cover of the circle is a 
light metal box carrying on one end the Y brackets of the telescope, and on 
the other a counterpoise to which is fixed a removable bracket carrying an 
adjustable mirror for illuminating the scales in the telescope and magnet, the 
mirror being also interchangeable with a lamp. The magnet box and torsion 
tube are fixed centrally above the instrument. The deflection bar is made 
channel-section of extremely hard metal, thus making it light and stiff. 

The telescope is of 8-in. focal length, fitted* with a high and low power 
eye-piece, striding level, and a longitudinal level fitted to the top side ; 
a glass diaphragm is placed in the focus of the telescope, which, instead of 
having the usual cross webs, has two scales engraved on it, one a long 
horizontal scale of 100 divisions, and the other a short vertical scale of 40. 

Two magnets are supplied, viz., the long or vibration magnet, and the 
short or deflected magnet. In the illustration the vibration magnet is 
shown with the inertia bar in its sheath. The N. end contains the ccllimator 
lens, whilst the S. end carries a piece of optical glass with a horizontal 
and vertical line engraved on it. 

The deflected magnet which takes the place of the reflector magnet 
in the Kew instrument, is fixed parallel to the collimator tube which carries 
a similar lens and engraved piece of glass as the vibration magnet. 

The magnets are suspended by means of a thin ribbon of phosphor 
bronze instead of the ordinary silk fibres, the ribbon being held both at the 
torsion tube head and magnet by improved clip chucks. With this suspension 
the torsion is constant. 

Two spare reels of ribbon are supplied fitted in boxes. 
Thermometers are fitted to both magnet boxes. 

A finely divided plummet is provided, which is read by a collimating lens 
in front of the telescope object glass. 

A rigid tripod stand is supplied, arranged for closing up into small space, 
and together with the deflection bar is carried in a canvas and leather-bound 
case. 

Complete, and packed in a mahogany case with shoulder strap. 

No. PRICES. s. d. 

625. Kew Pattern Instrument 8c o o 

626. India Office Pattern (Captain Eraser s) fitted with vertical 

circle for taking azimuths. As made for the Indian, 

United States, and Canadian Governments ... ... 90 o o 

627. Examination and verification at Kew Observatory if re 

quired, extra 660 

(If without vertical circle a reduction of 5 will be made.) 



LONDON, YOKE AND CAPE TOWN. 



6 4 



T. COOKE & SONS, LIMITED, 



THERMOMETERS various. 




Fig. 98. 

LIVINGSTONE S MAXIMUM & MINIMUM THERMOMETERS. 



630. Divided on the stem, on ivory or 
metal scales, in mahogany or 
morocco case, per pair ... 



LENGTH. 

8-in. lo-in. i2-in. i4-in. 

s. d. s. d. s. d. s. d. 



30 





SIX S SELF-REGISTERINGi MAXIMUM and MINIMUM 
THERMOMETERS. 

631. Opal glass scale, enamelled tube, 

in open-back white-japanned tin 

case, best make, with magnet ... 13 o 15 o 17 o 19 o 

632. Zinc scale, in white-japanned tin 

case, with magnet... ... ... 80 10 o 12 o 14 o 




Fig. 100. 



633 . Opal glass scale, best grade, mounted 
on oak back with revolving bronzed 
brackets for windows ... ... 25 o 33 



40 o 45 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Thermometers- various. 




Fig. JOl. 

DIMENUON SELF-REGISTERING MAXIMUM and MINIMUM 
THERMOMETERS. 

LENGTH. 

8-in. lo-in. 12-in. i4-in. 

s. d. s. d. s. d. s. d. 

634. Opal glass scale in white-japanned 

tin case, best make, with magnet 120 150 180 210 

635. Zinc scale in white-japanned tin 

case, with magnet 80 no 14 o 17 o 

636. MAGNETS, for Six s and Dimenuon thermometers, grooved 

2^-in., 8d. ; 3-in., lod. 




Fig. 102. 




Fig. 103. 

STANDARD SELF-REGISTERING MAXIMUM or MINIMUM 
THERMOMETERS. 

640. Opal glass scale, engine-divided 

tube, in oak frame, each ... 16 o 20 o 

641. Kew certificates, 3/- extra. 

Goods forwarded at Purchaser s Risk. 

LONDON, YORK AND CAPE TOWN. 



66 



T. COOKE & SONS, LIMITED. 



THERMOMETERS-various. 

No. 8-in. 
644. Brewers, copper ... ... ... ... ... 3^- 
64^. Brass, sugar boiling 


io-in. i2-in. 

4/- 5/- 

7/6 
4/- 


646. Zinc minimum, suitable for cold storage ... 3/- 
647. Boxwood Ditto ... ... ... ... ... 1/6 


648. Incubator ... ... ... ... ... .. 2/6 


651. Household, in boxwood, porcelain or metal, i/- and upwards. 

^ . ^^^fj^^to^ 

- HiBflaM&aHHHBsnw^ 




J 


\ff ^yy^sgNjBJ 

Fig. 104. 




":> 


Fig. 10:"). 

652. Bath ; porcelain, 3/6; japanned tin case, 2/- to 4/- ; whitewood, i/- 
653. School or public building, bold porcelain, 4/6 and upwards. 

Chemical Thermometers, with engine divided tubes, best quality, in 
turned mahogany boxes: 

6*54. 8-in. to 220 F, or corresponding C A (\ 


6^. lo-in. , 220 F 


C f) 


656. i2-in. ,, 300 F ,, 
657. i2-in. ,, 400 F ,, 


6 6 

7 6 


658. i4-in. ,, 500 F ,, 


8 6 


659. i4-in. ,, 600 F ,, 


a 6 


660. i6-in. ,, 700 F ,, 




Ditto of cheaper quality, engraved stems, turned cases : 
663. i2-in. to 220 F or corresponding C 




664. i2-in. ,, 300 F ,, 


7 6 


665. i4-in. ,, 400 F ,, 


J u 


666. i6-in. ,, 700 F ,, - ... ... ... . . 


A K 


667. Armoured Cases for chemical thermometers, any length, 
each ... ... ... ... ... *... ... n n 


668. Ivory tusk Thermometers : 6-in., 22/- ; 7-in., 28/- ; 8-in. 

66q. Silver-mounted Thermometers, to hang or stand : 
4-in., 22/- ; 6-in., 26/- to 357 

670. Hicks patent alarm Thermometer, including bell, batte 
board, etc. 


. 4 2/- 

- ; 8-in., 4o/-. 

ry, indicating 
2. i os. od. 





LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



67 



CLINICAL THERMOMETERS. 



Fig. 101. 



^ 



2-min. 
5. d. 
2 6 



i-min. i-niin. 
5. d. s. d. 

3 6 
5 o 



674. 4-in., plain tube, in nickel case ... ... 2 t> 3 o 

675. 4-in., lens front ,, ,, 30 40 

The above are provided with our own certificates, which we guarantee 
are within one-tenth degree of a corresponding certificate issued by Kew 
Observatory. 

The same thermometers without certificates, 6d. each less. 

676. Hicks patent lens front, with his own certificate 46 

677. Hicks "Facilis," easy to shake down, with lens 

front. Fig. 107 ... ... ... ... 5 o 

678. Ditto with plain front 26 3 

679. Veterinary thermometers, with normal temperature for various animals, 

marked on stem 4/- to 6/-. 

A few clinicals of different patterns, with Kew certificates, are kept in stock. 



5 6 

6 o 
6 



6 6 




No. 



Fig. 10!). 



682. MASON S WETJAND DRY BULB HYGROMETER, opal 
scales, engine-divided tubes, on oak board, small, 2$/- ; 
medium, 3o/- ; large ... 




Fig. 110. 

683. ADMIRALTY PATTERN HYGROMETER, zinc, well 

protected 

684. Kew Certificates for Hygrometers 

685. HYPSOMETER, complete, portable, of best construction, 

with one thermometer, divided to T \- degree 

686. Extra Thermometers for use with above, in metal cases 



i 15 o 



o 15 o 
060 

215 o 
o 15 o 



LONDON, YORK AND CAPE TOWN. 



68 



T. COOKE & SONS, LIMITED, 



Meteorological Instruments, etc. 




(MA* 




Fig. 111. 



689. GLAISHER S Rain Guage, with graduated 

glass measure complete, 8-in. diameter ... 

690. Ditto in galvanized iron, 22/- 

691. SYMONS ditto 5-in. diameter 

692. HOWARD S ditto with flint-glass bottle 

and graduated measure, 5-in- diameter ... 

693. HOWARD S Pedestal Rain Guage, with 

graduated tube, showing amount of 
rainfull without using a measure, i2-in. 
diameter 

694. GLAISHER S Tropical Rain Guage, extra 

large size, with tap and graduated 
measure 30 

695. Measuring Glasses for rain guages, 5-in., 2/- ; 8-in., 3/- 



Copper with 
brass ring. 

*. d. 

I 10 


Japanned tin 
with 
brass ring. 

,. d. 
o 18 o 


o 18 o 


10 


O 12 O 


090 



300 




Fig. 113. 

698. REGISTERING RAIN GUAGE, zero setting, showing T ^ r in. 

to i2-in. fall, in square japanned tin case, lo-in. x 8-in. 

699. DITTO in copper case... 



15 



* ^ 

3 18 o 

4 12 o 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



69 



Meteorological Instruments, etc. 




701 



702. 
703. 



Fig. 114. 

RECORDING RAIN GUAGE, runs for a week, showing 
rainfall in inches and T ^-ths at the exact time at which 
it occurred. With 8-in. funnel and including charts for 
one year 

Extra charts, per year s supply 

Rainfall Charts, per dozen 



12 10 
o 6 

o s 



707. 

708. 
709. 



710. 




Fig. 115. 

METEOROLOGICAL SET, consisting of standard maximum and mini 
mum thermometers and hygrometer, mounted on oak board, with 
Kew certificates ^"4 T 5 S - od. 

DITTO smaller size, without Kew certificates 3 55. od. 

DITTO consisting of 5-in. aneroid barometer, Mason s hygrometer, 
Six s thermometer, 8-in. boxwood thermometer, 5-in. japanned 
Howard s rain guage with glass measure, and record calendar for 12 
months. Packed in a stained deal case ... 2 os. od. 

Meteorological pads, for one year each is. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



Meteorological Instruments, etc. 




No. 
713 



Fig. 116. 



UNIVERSAL SUNSHINE RECORDER, with cards for 

one year 
714. DITTO with metal-dial bar needle compass in base 

Additional Cards for above, sufficient for one year, viz. : 
150 summer solstice, 150 winter solstice, and 100 equin 
octial 



7I5- 




Fig. 118. 

716. HYDROMETER, glass, for testing spirits, paper scale 

717. DITTO ivory scale 




Fig. 119. 

SIKES HYDROMETER, brass, complete in case, with 
measure and book of instructions : 

718. Pocket size, as illustrated 

719. Excise pattern ... 

720. COMPARATIVE SCALES for ditto, each 

721. SALINOMETER, glass 

722. ACCUMULATOR HYDROMETER 

723 PETROL 

724. LACTOMETER 



13 o 
13 10 



o o 



026 
030 



300 

2 l6 O 

040 

066 

026 
026 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS; LIMITED, 



STANDARD RAIL TEMPLATES. 

MESSRS. T. COOKE & SONS, LTD. have been appointed by the Engineering 
Standards Committee the sole makers of Templates for standard section 
tramway rails, bull-headed and flat-bottomed railway rails. The following 
are the prices of commercial sets, made of nickel, each of which has been 
verified by comparison with the standard reference templates made by them 
selves and deposited at the National Physical Laboratory at Bushy. The 
prices include a N.P.L. certificate to the effect that they have been so tested, 
and that their accuracy is within - of an inch. 



TRAMWAY RAIL TEMPLATES. 

The set of Templates for each weight of straight and corresponding 
curved rail (Report No. 2*) comprises fourteen pieces, and the prices are as 
follows : 







WEIGHT OF RAIL. 








XT f 








No. 


"B.S." Section. 


Straight. 


Curved. 


Price 


per Set. 






Ibs. per yard. 


Ibs. per yard. 





S. d. 


729 


i and ic 


90 


9 6 


9 


9 o 


730 


2 and 2c 


95 


101 


9 


9 o 


73 1 


3 and 30 


100 


1 06 


9 


9 o 


732 


4 and 40 


105 


III 


9 


9 o 


733 


5 and 50 


no 


116 


9 


9 o 



If made in Steel, ao/- per set extra. 
*Specification and sections of British Standard Tramway Rails and Fish Plates, 2i/- nett. 

BULL-HEADED RAILWAY RAIL TEMPLATES. 

The set of Templates for each weight of rail (Report No. 9!) comprises 
three pieces, and the prices are as follows : 



736. 

737- 
738. 

739- 
740. 
741. 
742. 
743- 
744- 



Weight of Rail 

in Ibs. per yard. 

100 

95 
9 

85 
80 

75 

70 

65 
60 



Price per Set. 






s. 


d. 


5 








5 


o 


o 


5 


o 


o 


5 


o 


o 


5 


o 


o 


4 


IO 





4 


IO 


o 


4 


IO 





4 


IO 






If made in Steel, i2/- per set extra, 
t British standard specification and sections of Bull-headed Railway Rails, 10/6 nett. 



LONDON, YORK AND CAPE TOWN. 



72 T. COOKE & SONS, LIMITED, 



FLAT-BOTTOMED RAILWAY RAIL TEMPLATES. 

The set of Templates for each weight of Rail (Report No. n*) comprises 
three pieces, and the prices are as follows : 



747- 

748. 

749- 
750. 
751- 
752. 
753- 
754- 
755- 

756. 
757- 
758. 

759- 
760. 
761. 

762. 
763. 

If made in Steel, io/- per set extra. 
^British standard specification and sections of Flat-bottomed Railway Rails, 10/6 nett. 

FIELD OR MARINE BINOCULARS of best quality. 



Weight of Rail Price per Se 
in Ibs. per yard. S. d. 


100 


5 


5 


O 


95 


5 


5 





90 


5 


5 


O 


85 


5 


5 


O 


80 


5 


o 


O 


75 


5 


o 





70 


5 


o 


O 


65 


5 


o 


O 


60 


5 










If made in Steel, i2/- per set extra. 






55 


4 


10 





50 


4 


IO 


O 


45 


4 


IO 


o 


40 


\ 


IO 


o 


35 


4 


2 


6 


30 


4 


2 


6 


25 


4 


2 


6 


20 


4 


2 


6 




Fig. 120. 



SIX LENS, low or medium shape, covered morocco leather, with japanned 
tubes and shades, in black or brown leather sling case. 



In Brass. In Aluminium. 



No. 






i 


S. 


d. 


i 


S. 


d. 


771. 


ig lines, 


power about 3 


i 


18 


o 


3 


5 


o 


772. 
773- 


21 

24 


,, 3* 
4 


2 
2 


2 

6 


o 
o 


3 
3 


12 

18 


o 
o 


774- 


26 


M 4* 


2 


10 


o 


4 


5 


o 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



73 



Field or Marine Binoculars. 

TWELVE LENS, medium or tall shape, covered Russian leather, with 

japanned tubes and shades, in black or brown leather sling case. 
775. 19 lines, power about 4^ 2 10 o 400 

77 6 - 2I , 5 2 15 o 480 

777- 24 ,, 5| 3 2 o 4 17 o 

77&- 26 ,, 6 380 560 

The medium shape is recommended for general purposes. 

Any of the above glasses, in aluminium, can be had with bright tubes at 
an extra cost of 2/6. 

Any 19, 21, or 24 lines glass can be had with covered instead of japanned 
shades, at the same price. 

780. Brown or black leather cases with sling strap for above, 7/6. 



OPERA GLASSES. 




Fig. 121. 

784. OPERA GLASS, half-pear shape, japanned 

mounts, covered morocco leather, in soft case 

785. DITTO conical shape, with rolled gold mounts, 

straight bars 

786. DITTO half-pear shape, gilt mounts, covered 

Russia ... ... ... ... i i o 

787. DITTO aluminium and pearl, Duchess, pearl 

heads and draws, superior lenses 

788. DITTO tortoiseshell and gilt, enamel bands ... 

789. DITTO aluminium and tortoiseshell, half pear 

shape, polished mounts 

790. DITTO gilt mounts, bent bars, and heads 

japanned aluminium ... 

791. DITTO ivory and enamel, gilt mounts, ivory 

heads, with handle 

792. DITTO aluminium and tortoiseshell, Duchess, 

enamel bands, with fixed handle 



* <*. 

15 o 

0180 

1 4 o 

2 10 O 



i 5 o 



2 12 O 



* * 

17 6 

1 2 O 

1 7 o 

2 15 O 

i 13 o 

120 

1 13 o 

II3O 

2 15 O 



LONDON, YORK AND CAPE TOWN. 



74 _ T. COOKE SONS, LIMITED, 

Opera Glasses. 

793. OPERA-FORM THREE-CHANGE GLASS, 

theatre, field, and marine, half-pear shape, 

japanned mounts, covered morocco iioo 1126 1150 

A number of other sizes and patterns are kept in stock, with and without 
handles. 

AITCHISON S PATENT ALUMINIUM COLLAPSIBLE FIELD GLASSES :- 

797. No. i, 6 lens ...... 2 IDS. od. 

No. 2 I2 ...... - S. od. 



DRAW BINOCULAR, aluminium, in solid leather sling case : 

799. Small ......... i 8s. od. 

800. Large ......... ^"2 8s. od. 



PRISMATIC BINOCULAR GLASSES. 

Prismatic glasses are now largely used in place of the old form of 
Binoculars, on which they are a distinct improvement. They possess the 
advantages of higher power and proportionately larger field of view, and are 
adjustable for interocular distance as well as for any difference of focus 
between the eyes. 

Monoculars can also be had, which being of less than half the size and 
weight, are very portable, and suitable for use on horseback. They can be 
had in either black or brown leather sling cases. 

GOERZ TRIEDER BINOCULARS. 




Fig 122. 

No. Power. Field. Monocular. Binocular. 

805. x 3 13-3 250 5 15 o 

806. x 6 6*7 2 15 o 6 10 o 

807. x 9 4-4 300 750 

808. x 12 3-3 400 9 10 o 

809. Eye-cups (spare) for above, 3/- each. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



75 



ZEISS PRISM BINOCULARS. 

These have the advantage of increased stereoscopic effect, which is 
obtained by the object-glasses being placed further apart than the eye-pieces. 
Those marked "night" are particularly serviceable for observation in the 
dusk or in foggy weather. The combined day and night glass is fitted with 
revolving eye-pieces, and is very suitable for use at sea. 

The Monoculars, of course, have no stereoscopic effect. 




Fig. 123. 



No. 

8ll. 

812. 

813- 
814. 
815. 
816. 

817. 
818. 

819. 



Power. 


Field. 


Monocular. 


x 4 


9*3 


2 10 





x 6 


6-2 


2 I 5 


o 


x 8 


4-6 


3 o 





x 5 (night) 


6-9 


4 o 


o 


* 7* 


5 3 


4 





X 10 


3 4 


4 5 


o 


X 12 


2-7 


4 5 






Binocular. 

5 10 o 
600 

6 10 

8 15 

8 15 

9 5 
9 5 



5 & io(combined ]6 9 
day & night) (3-4 



5 10 



Eye-cups (spare) for above, 2/6 and 3/- each. 



Also Prismatic Binoculars and Monoculars by Busch, Ross, Voigtlander, 

and other makers. 

822. ZEISS REVOLVER TELESCOPE, small, with eye 

pieces magnifying 12, 18 and 24 times, on tripod stand ... 22 o 

823. DITTO large, with eye-pieces magnifying 12, 25 and 

40 times, on tripod stand ... 29 o 

824. ZEISS HINGED STEREO-TELESCOPE, with single eye 

pieces, magnifying 15 times, on tripod stand 25 o 

825. DITTO with revolving eye-pieces, magnifying 10 and 18 

times, on tripod stand 31 o 



LONDON, YORK AND CAPE TOWN. 



76 T. COOKE & SONS, LIMITED, 



TERRESTRIAL and NAVAL TELESCOPES, 




Fig. 124. 
No. 

828. COASTGUARD TELESCOPE, object-glass 3-in. aperture, with one 

draw, brass bronzed, leather covered body, pancratic eye-piece and 
dew shade, leather sling and caps, mounted on tall tripod stand, and 
packed in a varnished deal case, complete ... ... ij ics. od. 

829. TELESCOPE, object-glass 2|-in. aperture, with terrestrial eye-piece and 

tripod, in pine case 10 os. od. 

A separate catalogue of astronomical instruments may be had on application. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE SONS, LIMITED, 



77 




Fig. 125. 

830. TELESCOPE, with object-glass of 3-in. aperture, power 45, taper brass 
leather-covered body with leather sling and caps, rack focussing motion 
and draw to eyepiece, on brass folding table tripod 10 os. od. 




Fig. 126. 

831. DRAW TELESCOPE, with three, four, or five draws, brass-bronzed, 
leather-covered body, pancratic eye-piece, dew shade, leather sling and 
caps. 

APERTURE OF OBJECT-GLASS. 



i-in. 


if-in. 


2-m. 


2j-in. 


2^-in. 


2f-in. 


s. d. 
44 


s. d. 
500 


s. d. 
5 18 o 


s. d. 
700 


. d. 
8 10 o 


r~r d. 

10 10 



832. DITTO as above, but of fixed power and without leather sling and caps. 

ii-in., ^"2 los. od. ; if-in., ^"3 os. od. 




Fig. 127. 

833. NAVAL TELESCOPE with one draw, brass-bronzed, leather-covered 

body, pancratic eye-piece, dew shade, leather sling and caps. Sizes 
and prices as Draw Telescopes No. 831. 

834. "OFFICER-OF-THE-WATCH" TELESCOPE, with one draw, object- 

glass of i^-in. aperture, power 15; 23f-in. long when open, i8-in. 
when closed. With leather-covered body and cap ^"2 tos. od. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



COOKE LENSES FOR PHOTOGRAPHY. 

H. D. Taylor s Patents. 

In their freedom from astigmatism and curvature of field, these lenses are 
a distinct advance on everything preceding them. With their large Apertures 
they are specially suited for all rapid and accurate work requiring uniformly 
fine definition. 




Fig. 128. 

vSectional view of a COOKE LENS, showing its three simple glasses and the 
screw adjustments by which final perfection is obtained. 

These lenses are constructed of particularly pure, transparent, and durable 
glasses, and their images are remarkably free from all traces of flare and 
ghost, or other results of surface reflections. 

SERIES III. Full Aperture f/6-5. 



No. 
Lens 
and 
Flange. 


All dimensions in inches. 


PRICE 

Lens with 
Iris Diaph 
ragm. 


S. 

- -, 

Patent 
Flange, 
extra. 


Approx. 
equivalent 
focus. 


With large 
aperture to 
cover plates. 


When 
stopped down 
to 
cover plates. 


Diameter 
of Flange 
Screw. 


Diameter 
of 
Hood. 


838 


4.25 


3i x si 


5 x 4 


1-25 


1*13 


3 I2S. 2/- 


8 39 


5 


4t < 3t 


7 x 5 i 5 


1-25 


\ s - 


a/- 


840 


5 5 


4i x 3i 


8x5 1-5 


i 4 


A 5s- 


/ 


841 


6 


5 x 4 


8i x 6i 1-5 


1*4 


A i os. 


*/ 


842 


7*5 


6* x 4t 


10 x 8 


I 5 


1-65 


5 IOS - 


/ 


843 


8-25 


7 x 5 


ii x 9 


175 


2 I 


6 is. 


z/- 


844 


ii 


8i x 6i 


14 x ii 2-25 


2 5 


lQ IOS. 


2/3 


845 


*3 


10 x 8 


17 x 14 


2 5 


2-8 


*5 os - 


2/6 



MOTE. Messrs. T. Cooke & Sons being unable to cope with the large demand for these 
lenses in addition to their ordinary business, have appointed Messrs. Taylor, Taylor & Hobson, 
of Leicester, their Sole Licencees for the British Isles, and they are now manufacturing the 
Cooke lens for them with the greatest success. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



79 



^r ~/ i .-^-,7 



SERIES Y. Full Aperture f/8. 





All dimensions in inches. 


PRICES. 


No. 
Lens 
and 
Flange. 


Approx. 
equivalent 
focus. 


With large 
aperture 
to cover 
plates. 


When 
stopped down 
to cover 
plates. 


Diameter 
of 
Flange 
Screw. 


Diameter 
of 
Hood. 


Lens 
with Iris 
Diaphragm. 


- -~ 

Patent 
Flange, 
extra. 


849 


4*25 


3i x 3i 


5 x 4 


1-25 


I-I5 


2 i8s. 


2/- 


850 


5 


4t x 3i 


6i x 4i 


l-2 5 


I I5 


^3 3s. 


2/- 


851 


5*5 


4i x 3i 


7 x 5 


1-25 


I-I5 


^"3 8s. 


2/- 


8 5 2 


6 


5 X 4 


8x5 


1-25 


1*15 


^3 I2S - 


2/- 


853 


7*5 


6| x 4 | 


8| x 6 


l 5 


r 4 


A IOS - 


2 / 


854 


9 


8x5 


12 X IO 


i 5 


1-65 


5 IOS - 


2/- 


855 


ii 


8J x 6 


15 X 12 


175 


2*1 


7 i5s. 


2/- 


856 


13 


10 x 8 


17 x 15 


2 


2 5 


^"10 os. 


2 /- 


857 


16 


12 X 10 


18 x 16 


2 5 


2-8 


2*15 OS- 


2/6 


858 


18 


15 X 12 


24 X 20 





3 3 


18 los. 


3A 


859 


24 

1 


18 x 16 


27 x 24 


4 


4-25 


30 os. 


4/- 



Larger Sizes to order. 



FLANGES for attachment to cameras are charged extra because the 
Royal Photographic Society s Standard Screws are now so common, and 
our methods of making interchangeable screws so accurate, that it is not 
necessary to buy a flange with every lens. 

STANDARD ADAPTERS are made to carry lenses in flanges larger than 
their own. 

PAIRING LENSES FOR STEREOSCOPIC WORK. We can usually 
select from stock and without extra charge pairs of Cooke Lenses having the 
same equivalent focus; but if it is required that they shall be identical also in 
back focus, that is, the focus as measured from the flange screw shoulders, we 
make an extra charge of 7/6 for thus matching them. 



Cooke Lenses received in 1895 * ne cmly medal given annually for 
inventions of sufficient merit by the Royal Photographic Society. 

Also Focussing and Extension Cooke Lenses, Cooke Portrait Lenses, 
Cooke Lenses with shutters, and Cooke Lenses for process work. Descriptive 
booklet free on request. 



LONDON, YORK AND CAPE TOWN, 



8o 



T. COOKE & SONS, LIMITED, 



FIG. 3 





C 









FIG. 2. 




FIG 1. 



LONDON, YOEK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 81 

ON THE ADJUSTMENT OF 

GOOSE S FjEYBI^SIBLB IlEVELi. 



THIS Instrument has been specially designed with two objects in view; first to afford an 
easy, efficient, and at all times available means of adjusting the line of collimation of 
the telescope to perfect perpendicularity to the vertical axis of the instrument ; and secondly, 
to obtain a form of construction in which elegance and great compactness are attained, and 
strength and rigidity are secured to the instrument where most required, rendering it far less 
liable to be deranged by careless handling, which is almost inevitable under some circum 
stances, than the older well-known forms of reversible levels, notably the Y Level, all the 
advantages of which are retained in this instrument, whilst its objectionable features are avoided. 

A general view of the Level is given on page 19, and its construction is shown opposite, 
where Fig. i is the telescope (shown in longitudinal section), which bears two perfectly equal 
cylindrical flanges F and F turned on it concentrically with the tube, being essentially similar 
to the telescope of a Y Level. The cross-lines, consisting of one horizontal line and two 
subsidiary vertical lines, are ruled upon parallel glass carried by a perforated block in the eye 
end, which is adjustable vertically to correct collimation by the two antagonistic screws d and 
d. The object-glass is made to approach to, or recede from the cross-lines for focussing, by 
turning the milled head M. 

The two flanges F and F , instead of resting upon two Y s, fit perfectly within two 
corresponding collars S and S , which latter form the ends of the rigid socket S-S-S . The 
two flanges F and F and their corresponding collars S and S being exactly equal, the telescope 
tube can be introduced indifferently from either end of the socket S-S-S and pushed home 
until the stop-flange St comes in contact with the socket end. The telescope can be further 
secured in its socket by the screw Sc. 

One end S of the socket is furnished with a threaded bolt which passes through a hole in 
the base-plate P-P and is adjustable vertically, and locked by the two lock-nuts N and N. 

The adjustment of the socket S-S-S 7 so that its axis of figure may be exactly at right 
angles to the vertical axis B, is effected thus : 

First, some minute and well-defined test object, which need not necessarily be on the same 
level or height as the instrument, is selected. A small needle-hole in a piece of paper, fixed 
not less than 20 feet away, forms a convenient mark ; but if the instrument requires adjustment 
in the open field, where perhaps the above-mentioned mark cannot be made use of, it will be 
most likely an easy matter to select some immovable and sufficiently well-defined test-mark 
from the features of the surrounding landscape. The instrument is mounted firmly upon its 



LONDON, YORK AND CAPE TOWN, 



82 T. COOKE & SONS, LIMITED, 



stand in such a manner that when the telescope is directed towards the test-mark, it may then 
lie directly over one of the foot-screws. The eye-piece is carefully pushed in or out in its tube 
until the cross-lines are seen as distinctly as possible, and the telescope is then focussed upon 
the test-mark, and with the aid of the foot-screw the image of the latter caused to fall nicely 
upon that part of the horizontal line lying midway between the two vertical lines. All error of 
parallax must now be corrected. If, when the eye is moved gently up and down the eye-piece, 
the image of the test-mark does not move in the slightest degree with respect to the horizontal 
cross-line, then the telescope is correctly focussed ; but if the image seems to follow the move 
ments of the eye, that is to tend to move above the cross-line when the eye is raised, and to 
move below it when the eye is lowered, then the image is not focussed exactly upon the cross- 
line, but lies on the side of the cross-lines towards the object-glass. The object-glass must 
now be caused to approach the cross-lines by means of the milled head. If the image of the 
test-mark should apparently move in a direction contrary to that of the eye. that is to tend 
to move below the cross-line when the eye is raised, and vice versa, then the image lies nearer 
to the eye than the cross-lines, and the error is corrected by moving, with the aid of the milled 
head, the object-glass farther away from the cross-lines. After all parallax has been removed 
and the test-mark carefully bisected by the cross-line, the screw Sc is taken out and the 
telescope is withdrawn carefully from its socket, and when right out, the socket is turned round 
with the other hand, end for end, and then the telescope is carefully pushed home again. The 
telescope is now reversed in its socket, or more correctly the socket is reversed upon the 
telescope. Care should be taken that no dust is allowed to settle upon the flanges of the 
telescope during its insertion, and that the hole in the stop-flange S through which the screw 
Sc passes, is kept vertically below the centre of the tube when the telescope is pushed home, 
so that the single line in the eye end may be as horizontal as possible, If on re-directing the 
telescope towards the test-object, the image of the latter is no longer bisected by the cross- 
line, but falls either above or below it, then the foot-screw below the telescope is turned until 
the image of the test-mark is brought as exactly as possible half-way back towards bisection 
by the cross-line. The lock-nuts N and N are then loosened sufficiently to allow them to 
be turned by a moderate pressure on the end of the lever used for their adjustment, and the 
end S of the socket is raised or lowered until the test-mark is again nicely bisected by the 
cross-lines, after which the operations of reversal of the telescope in its socket, and the 
correction of the error half by the foot-screw and half by the lock-nuts N and N are repeated 
until the bisection of the image is as nice and exact as possible, and remains quite undisturbed 
by the reversal of the telescope within its socket. 

If it be thought necessary to adjust or examine the collimation of the telescope, the test- 
mark is carefully bisected by the cross-line, and then the screw Sc is withdrawn and the 
telescope is carefully twisted or rotated half-way round in its socket, so that the screw-hole 
through which Sc passes is brought to the top, and the cross-line is again horizontal. If the 
image is not now bisected, but falls above or below the cross-line, the error or deviation is half 
corrected by means of the foot-screw lying under the telescope and then the image is caused 
to be bisected by the cross-line by adjusting the latter by means of the antagonistic screws 
d and d. The telescope is twisted half-way round again and any remaining error corrected 
as before; if necessary, the operation is repeated until accuracy is attained. 

This adjustment, if required, should precede the adjustment of the socket. 

In order to adjust the bubble-tube, the instrument is first set as nearly level as the operator 
is able to judge, by means of the three foot-screws. The telescope is then turned in a direction 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 83 



as nearly as possible parallel to the line joining two of the A 

foot-screws. If A, B and C represent the three foot-screws, then n \ 

the telescope is directed along the line d e which is parallel to 

the line joining B and C, and by means of the two foot-screws d C 

B and C the bubble is brought to the centre of its run, so that 1 

both ends of the bubble read the same. The telescope is then ^ I 

turned round end for end, one-half revolution, and if the 
bubble now departs from the centre of its run it is brought 
half-way back again by one of the foot-screws B or C and the 
other half of the error is corrected by means of the lock nuts | Q 

R and R. For example, if, on the telescope being reversed on 

its axis, the bubble comes to rest eight divisions away from its previous central position, then 
by one of the foot-screws B or C the bubble is caused to move back four divisions and the 
remaining four divisions are corrected by means of the lock-nuts R and R. Both ends of the 
bubble should now give the same reading. The telescope is now turned at right angles to its 
former position so that it lies directly over the foot-screw A along the line n o, and the foot- 
screw A is turned until the bubble gives similar readings at both ends. The telescope is then 
reversed, and any deviation (which will be very slight) of the bubble is half-corrected by the 
foot-screw A and half by the lock-nuts R and R. The bubble tube should now be approxi 
mately correct in its adjustment, and any further exactitude may be obtained by a continuation 
of the above method, the telescope being directed along either of the lines d e or n o. and 
care being taken to allow the bubble time to settle to its rest after each reversal of the 
instrument. 

After adjustment the telescope ought to lie in its socket with its stop-flange St against 
the end S of the socket, so that it may be secured by the screw Sc. 



LONDON, YOEK AND CAPE TOWN. 



84 T. COORE & SONS, LIMITED, 



d- 




Cooke s Pattern Transit Theodolite. 

with centering arrangement to stand. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 85 



ON THE ADJUSTMENT OF 

HBODOLITB 



A GENERAL view ot Cooke s pattern of transit theodolite is shown in the drawing on the 
opposite page, which represents a 5-inch instrument, that is to say, one in which the 
diameter of the circles is 5 inches. 

All instruments are carefully examined and adjusted before leaving the works, but in case 
of rough handling or possible accidental injury while in use, it is very desirable that from time 
to time the various adjustments should be tried and proved, without which it is impossible 
for the Engineer to have any certainty as to the accuracy of his work. 

For this reason he should make himself thoroughly acquainted with the details of his 
instrument, so that at any time he may be able to perform the necessary corrections for him 
self. With a view to simplifying this operation, the method of carrying out the various 
permanent adjustments of this pattern of transit theodolite is here given, and it is recommended 
that they be performed in the order named. 



I. Adjustment of the levels on the horizontal plate perpendicular to the vertical 
axis of the instrument. 

Having set up the instrument firmly on good solid ground, release the lower clamping 
screw and turn the head until the longer of the two levels lies in a direction parallel to an 
imaginary line joining the centres of two of the foot-screws. The shorter tube then lies towards 
the third. Now level the instrument by means of the foot-screws, so that both bubbles lie in 
the middle of their runs. Then turn the head of the instrument one half round in azimuth, 
that is to say, through an angle of 180 degrees. If the bubbles remain true they are in perfect 
adjustment, but if not, then by means of the capstan-headed lock-nuts (c c] by which the 
larger one is attached to the horizontal plate, correct it for half the error only, and for the 
other half by means of the foot-screws. 

Now complete the revolution of the head, bringing it to its first position, and again notice 
this bubble. If it is not quite exact, the same operation must be repeated, that is to say, half 
the error must be again eliminated by means of the capstan-headed nuts, and the other half 



LONDON, YORK AND CAPE TOWN. 



86 T. COOKE & SONS, LIMITED, 



by means of the foot-screws. By repeated trials this level can thus be eventually exactly 
corrected, after which the smaller bubble may be compared with and adjusted by it, and when 
the head of the instrument can be twisted through an entire revolution without disturbing 
either of the bubbles from their positions in the middle of their runs, the levels are in perfect 
adjustment. 

The same adjustment can be made by reference to the level which is mounted on the 
vernier arms of the vertical circie, sometimes called the azimuth level. This bubble is of more 
delicate construction than those on the horizontal plate, so that by its use greater accuracy 
may be attained. It must first be carefully corrected, so that the head of the instrument may 
be turned in azimuth through an entire revolution without disturbing the position of the 
bubble, after which the levels situated on the horizontal plate can be compared with and 
adjusted by it. The operation is, however, of somewhat longer duration, and as the method 
given above will be found sufficiently accurate for all practical purposes, no further description 
of it is given here. 



II. Adjustment of the central line of vision of the telescope perpendicular to the 
transit axis. 

This is horizontal collimation, and is effected by means of the pair of antagonistic screws 
(b b) situated near the eye end of the telescope. 

Having carefully levelled the instrument, direct the telescope to some small object, such 
as a pin-hole in a piece of white paper, fixed at as great a distance as can be distinctly seen, 
and by means of the lower tangent screw bring the centre of the webs to fall exactly upon it, 
all clamps being firm. Now having turned back the covers of the bearings and loosened one 
of the clipping screws (e e] at the lower extremity of the vernier arm, gently lift the upper 
part of the instrument and reverse the transit axis in its bearings. Release the clamp to the 
vertical circle and then transit the telescope, after which again direct it to the previous object. 
If it falls exactly on the cross-hairs the adjustment is perfect, but if not, correct half the error 
only by means of the antagonistic screws (b b) and then repeat the operation. This time it 
will be found to be almost, if not quite, correct, but if necessary again divide the error by 
means of the screws, and so on until the adjustment is perfect. 

No adjustment is provided or required for vertical collimation with this instrument. 



III. Adjustment of the transit axis so as to be truly horizontal. 

This adjustment is effected by means of the antagonistic screws (a a) situated just below 
one of the Y bearings, and can be carried out with the aid of a striding level. It is an adjust 
ment that is not likely to require much attention, for having once been carefully corrected by 
the maker of the instrument nothing but very rough usage can possibly displace it again.. 

Having levelled the instrument carefully by means of the bubbles on the horizontal plate 
and noticed that this adjustment is perfect, turn back the caps which cover the ends of the 
transit axis in its bearings. Now erect the striding level on the top of the axis just over the 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 87 



bearings, and observe it carefully. (Reverse it, in order to examine its own adjustment, and 
if any error be discovered, this must be corrected before proceeding further). If the bubble 
does not remain in the middle of its run. it must be made to do so by slightly opening or 
closing the slit in the bottom of the adjustable Y, by means of the antagonistic screws (a a), 
which has the effect of lowering or raising that end of the transit axis. When the adjustment 
is completed for one position, the bubble in the striding level ought to remain steady while 
the head is twisted in azimuth through an entire revolution. 

This same adjustment may be accomplished without the aid of a striding level in the 
following manner : Set up the instrument at about forty or fifty feet distance from a high wall 
or other object of considerable elevation, level it carefully, and direct the telescope to some 
small point situated as high up as possible, and bring the cross lines to bear exactly upon it. 
All parallax must now be carefully eliminated by means of the focussing screw and by gently 
moving the eye-piece in or out of its socket until the cross lines and the object are brought 
exactly into the same focus. Then tilt the telescope and make a small mark on the wall near 
to the foot, at the point of intersection of the cross lines. Now turn the telescope 180 degrees 
in azimuth, transit it, and again direct it to the upper mark, after which tilt it as before and 
see if the point of intersection of the cross lines exactly corresponds with the lower mark. If 
it does so the transit axis is truly horizontal, but if not. half the error must be corrected by 
means of the antagonistic screws (a a) as previously described, and the operation repeated in 
order to ensure accuracy. 



I Y. Adjustment of the level attached to the vernier arms of the vertical circle, so 
that when the central line of vision of the telescope is horizontal, and the 
zero lines of the vertical verniers coincide with the zero diameter of the 
vertical circle, the bubble may be in the middle of its run. 

This adjustment is effected by means of the capstan-headed lock-nuts (d d) that attach 
the level bubble to the vernier arms. 

Having levelled the instrument carefully by means of the bubbles on the horizontal plate, 
bring the bubble in the azimuth level to the middle of its run by means of the antagonistic 
screws (e c] at the end of the clipping arm. Now set the zero diameter of the vertical circle 
to coincide exactly with the zero lines on the vertical verniers, and clamp it there. Observe 
an ordinary levelling staff held at as great a distance as it can be distinctly seen, and take the 
reading by the horizontal web. Now release the clamp and transit the telescope, and again 
adjust the zero diameter of the vertical circle to the zero lines on the verniers. Revolve the 
head in azimuth one half turn, bringing the telescope to its former position, and once more 
take the reading of the staff. If it is not the same as previously observed, correct half the 
error by the antagonistic screws at the end of the clipping arm and then repeat the operation 
until all error is by this means eliminated. When the adjustment is complete correct the 
azimuth level by means of the capstan-headed lock-nuts, so that the bubble remains in the 
middle of its run. 



LONDON. YOKK AND CAPE TOWN. 



88 



T. COOKE & SONS, LIMITED, 



NOTES ON THE CONSTRUCTION AND USE OF 

COOMB S SAGHEOMETE^S. 



ATACHEOMETER is a transit theodolite of which the telescope is provided with an 
extra lens for ihe purpose of converting it into a telemeter. 

English Engineers have been slow to take advantage of this instrument, which for 
distance-measuring purposes is much more expeditious and accurate than any system of 
chaining, especially over difficult ground. 

The use of the anallatic lens dispenses with the tedious addition to every reading of what 
is called the constant * of the instrument, which is always necessary in the case of theodolites 
merely provided with stadia lines. 

The diagram shows the arrangement of lenses usually employed. 



In order to overcome the loss of light occasioned by the introduction of the extra lens, 
the telescope of a tacheometer is made correspondingly larger than that of a theodolite, while 
at the same time eye-pieces of higher power are employed, which facilitate the reading of the 
stadia rod with accuracy. The eye-pieces are made to slide vertically across the eye-end 
by means of a rack-and-pinion movement, which enables a better view to be obtained of the 
outer pair of lines ; A very small movement suffices for this. 



\/ 



/ \ 



The lines on the diaphragm are usually ruled to read i in 50 between the outer pair, and 
i in 100 or i in 200 between the inner pair, and the anallatic lens serves to make these values 
constant for any distance. Readings taken on a staff on which the unit of measurement is 
divided into fifty equal parts will therefore be correct when the outer pair of lines is used, but 
the difference of the readings must be multiplied by two or four before reduction when taken 
with the inner pair. The ratio of i in 50 allows the foot staff to be divided throughout into 
JLths of a foot, a sufficiently open division to enable it to be read without error at a 
considerable distance. The metre staff is usually divided to two centimetres and halves, 
from which results to within one-half of a metre are easily obtained. 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



89 



Similarly readings taken on a staff on which the unit of measurement is divided into one 
hundred equal parts will be correct when the inner pair of lines, if set at i in 100, is used, but 
the difference of the readings must be divided by two before reduction when taken with the 
outer pair. Unfortunately divisions so small as y^th of a foot are only readable at short 
distances, so that frequently wider graduations such as J^th of a foot are used, although the 
staff is numbered to read in 



The centre line in the diaphragm being exactly at the half distance across either pair, it 
naturally follows that readings of i in 100, i in 200, or i in 400, as the case may be, are 
immediately obtainable. 

The circles are divided to 360 degrees as in theodolites, or to 400 grades. The latter is 
called the centesimal method, and was originated solely to facilitate the reduction of the 
readings, each right angle being composed of 100 grades of 100 centesimal minutes each, as 
against 90 degrees of 60 minutes each by the sexagesimal method. Tables and diagrams are 
now obtainable for both methods, so that nothing is gained by departing from the more 
familiar division of 360 degrees. 

The vertical circles of Cooke s Tacheometers are engraved with the zero at the top, 
therefore the 90 degrees and 270 degrees (or 100 grades and 300 grades) naturally correspond 
with the indices on the opposite verniers when the telescope is horizontal. When reading the 
circle it follows that angles less than 90 degress (or 100 grades) represent rising sights, while 
those greater denote falling ones. If the opposite vernier is used the determining angle is 
270 degrees (or 300 grades), so that whichever vernier is employed no confusion is possible. 

It is necessary that the position of the anallatic lens with reference to that of the object 
glass of the telescope shall be fixed and unvarying in order to obtain the best results. For 
this reason no attempt is made to provide for the adjustment of the measuring angle by moving 
it backwards and forwards in the tube as is done in the instruments of some makers. (This 
condition also requires that the adjustment to focus shall be at the eye-end of the telescope 
instead of at the object-end as in the case of a theodolite). The lines on the glass diaphragm 
which constitute the measuring angles are accurately ruled in the first instance to within 
louo o of an inch, so that no after adjustment of any kind is necessary. In the event of any 
diaphragm being broken or damaged, an exactly similar one can be obtained from the makers 
on quoting the number of the instrument. 

The adjustments of the tacheometer are similar to those of the transit theodolite already 
described, with the exception that an extra bubble is fitted to the telescope body which can 
be adjusted at the same time and in the same way as that attached to the vernier arms. 




The principle of the action of the anallatic lens in automatically referring all readings to 
the centre of the instrument may be explained as follows : 

Let be the object-glass, L the anallatic lens, and A the vertical axis of the instrument, 

S-S 

while S S is a staff or stadia rod held at such a distance that g -. = T , and let S A ; 

S A be two rays, which, if produced, would meet at A. But the effect of the object-glass 



LONDON, YORK AND CAPE TOWN. 



90 T. COOKE & SONS, LIMITED, 



upon these rays is to refract them so that they converge more rapidly, and after crossing each 
other at a they fall upon the anallatic lens L (which has a principal focal length = L a) 
at p and p respectively, and emerge therefrom as the parallel rays / n , I n. 

Now, if the staff be brought nearer to the instrument, say to s-s , then JT- = -j-^ as 

before, and the rays s-A, s A follow the same course as previously. Hence, if the stadia 
lines are placed so as to cut the parallel lines n-l, n I , it naturally follows that all readings 
are automatically referred to the centre of the instrument as required. 

The measurement of heights and distances by means of the tacheometer is effected as 
follows : A stadia rod being held vertically upon the point whose height or distance is re 
quired, the telescope is directed towards it at such an angle as will cause the outer pair of lines 
in the diaphragm to lie across it. Two readings of the rod, one by each line of the pair, are 
then taken and booked, and the difference between these two readings is called the generating 
number (G). But if the staff is at such a distance that its full length is insufficient to fill the 
space between the outer pair of lines, the inner pair should then be used, and the difference 
between the readings must be multiplied by two or four as the case may be to obtain the true 
generating number. 

The inclination of the telescope must then be read on the vertical circle and the angle 
booked. From the information now obtained the horizontal distance of the staff from the 
centre of the instrument and the difference of height between the centre of the telescope, and 
a point on the staff midway between the two readings, may be calculated. Much time and 
labour will be saved by the employment of a slide rule, a book of tables, or a reduction diagram. 



LONDON, YOKK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



INDEX. 



Abney s Levels. . 
Adj ustment of Levels 

Theodolites .. 

Admiralty Pattern Hygrometers 
Aitcheson s Field Glasses 
Alarm Thermometer 
American Pattern Transit 
Anemometers 
Aneroids 
Arrows, Chain 
Artificial Horizons 
Balance, Spring 
Band Chains 
Barometers 

Barker s Prismatic Compass 
Barographs 

Bath Thermometer :. 
Binnacle, Boat 
Binocular Telescopes 
Biram s Anemometers 
Boat Binnacle 
Boat Compasses 
Boiling-point Thermometer . . 
Books, Technical 
Boning Rods 
Box Sextants 
Brewers Thermometers 
Brunton-Pearce Pocket Transit 
Bubble, Circular 
Bubbles, Spare 
Builder s Level 
Canvas Cases 
Caps for Tripods 
Carved Oak Barometers 
Cases, Leather 
Cavalry Sketch Board 
Chain Arrows 

Chains, Land 

Steel Band .. 
Charts, Rainfall 
Cherub Ship-log 
Chemical Thermometers 
Circular Bubbles 
Circumferentors 
Clinical Thermometers 
Clinometer Compasses 
Clinometers 
Compasses, Boat 

Gimbal 

Magnetic 

Major Leigh s . . 

Night Marching.. 

Prismatic 
Cooke Lenses 
Cross Staves 
Current Meters 
Curves, Cards of 
Curve Tables 
Cushing s Levels 

Cross-Sight Attachment, Deacon s 
De Lisle s Clinometers 
Dials, Mining 
Dimenuon Thermometer 

Double Sights 

Drainage Level 



27 Dumpy Levels 

81 Everest Theodolites . . 

85 Field Books 

67 Field Glasses 

74 Fergusson s Surveying Circle 

66 Flags for Pickets 

8 Gas Leak Indicators 

57 Gas Pressure Gauges . . 

48 Gauge, Tide 

43 Gauges, Rain 

37 Gimbal Compasses 

61 Glasses, Marine and Field . . 

43 Glasses, Prismatic Binocular 

48, 52 Goerz Binoculars 

32 Gunsights 

56 Hall Barometers 

66 Harpoon Ship-log 
34 Headley Dials 

36, 75 Heliographs 

57 Heliotropes 

34 Hick s Clinical Thermometers 

34 Horse Standards 

67 Household Thermometers . . 

14 Hutchinson s Prismatic Compass 

40 Hydrometers 

37 Hygrometers 

66 Hypsometers . . 

25 Incubator Thermometers 

40 Indicator Paper, Metallic 

13,24 Indicators, Steam 

21 Lactometers . . . . . . . 70 

40 Land Chains . . . . . . . 42 

11,23 Chain Arrows .. .. . 43 

54 Leather Cases .. .. .. .11,23 

n, 23 Lenses, Cooke .. .. .. . 78 

29 Levelling Books . . . . . 14 

43 .. Staves 39 

42 Levels, Abney s . . . . . 27 

44 ,, Builder s .. .. . 21 
69 ,, Bolton s .. .. . 21 

38 Cooke s.. .. .. . 20 

66 ., Cushing s .. .. . 21 
40 , Drainage .. .. . 21 

24 , Dumpy . 21 

67 , Reflecting . . . . . 27 

25 , Spirit 13, 24 

26 , Striding .. .. . 12 
34 . Wye 

34 Littlejohn s Patent Head 

33 Livingstone Sets 

32 Livingstone Thermometer . . 

32 Logs, Ship 

31 Magnetic Compasses 

78 Magnetometers 

28 Magnets.. 

59 Major Leigh s Compass 

14 Major Verner s Prismatic Compass 

15 Marine Barometers .. 
21 Marine Glasses 

23 Maximum Thermometers 
26 Measuring Tapes 

24 Measuring Glasses 
65 Mekometers 

25 Mercurial Barometers 
21 Metallic Indicator Paper 



LONDON, YORK AND CAPE TOWN. 



T. COOKE & SONS, LIMITED, 



INDEX. continued. 



Meteorological Pads 69 

Meteorological Sets 69 

Meteorological Instruments . . . . 64 

Military Aneroids 49 

Minimum Thermometers . . . . 65 

Mining Dials 24 

,, Staves . . . . . . . 39 

M Innes Steam Indicator . . . 60 
Mountain Aneroids . . . -5 

Nautical Sextants . . . - 35 

Night Marching Compass . . 32 

Offset Rods 40 

Opera Glasses . . . . . . 73 

Optical Squares . . . .27 

Paceometers . . 60 

Pediment Barometers . . 53 

Pedometers .. .. . . 58 

Perambulators . . . . . . 59 

Photographic Lenses . . . .78 

Plane Tables . . . . . . 28 

Plumb-bobs .. .. . . 13 

Pocket Dials 25 

Pocket Transit, Brunton-Pearce . 25 

Poles, Ranging. . .. .. . 40 

Pressure Gauges, Gas. . .. . 60 

Prismatic Compasses .. .. . 31 

Binoculars.. .. . 74 

Prismatic Compass, Barker s . 32 

,, ,, Hutchinson s . 32 

,, ,, Major Verner s 32 

,, ,, Service Pattern 32 

Quadrants . . . . . . . . 34 

Rail Templates 71 

Rain Guages . . . . . . . 68 

Rainfall Charts 69 

Rangefinders .. 30 

Ranging Poles . . . . . . . 40 

Recess Rods . . 41 

Recording Rain Gauge . . . . 69 

Recording Barometers . . . . 56 

Reflecting Level . . . . . . 27 

Registering Rain Gauge . . . . 68 

Repair Outfit 43 

Richards Steam Indicator . . . . 60 

Road Tracers 26 

Robinson s Anemometer . . . . 58 

Rule Pattern Clinometers . . . 26 

Salinometers . . . . . . . 70 

Sectional Note Books.. .. . 14 

Self-recording Aneroids . . . 56 

Self-recording Thermometers . 56 

Service Pattern Compass . . . 32 

Sextants, Box . 37 

Nautical .. .. . 35 



Ship-logs 

Six s Thermometer 
Sketch Board, Cavalry 
Sopwith Staves 
Spring Balance 
Squares, Optical 
Stadia Rods 
Staff Papers 

,, Protectors 
Standard Aneroid 
Standard Barometer . . 
Standard Rail Templates 
Star Telescopes 
Staves 

Steam Indicators 
Steel Bands 
Tapes 
Striding Level . . 
Sunshine Recorders 
Surveying Aneroids 
Surveyors Rods 
Surveyors Walking Sticks 
Tacheometers 
Tapes, Constantia 
,, Linen 
Steel .. 
Technical Books 
Telescopes. Binocular.. 
Naval 
Star 

,, Terrestrial 

., Zeiss Revolver 

Templates, Rail 

Theodolites, Everest . . 
,, Railway . . 

,, Transit .. 

Thermographs 

Thermometers . . 

Tide Gauges . . 

Travelling Aneroid 

Trieder Binoculars 

Trocheameters . . 

Tropical Umbrellas 

Umbrellas, Tropical 

Walker s Patent Logs 

Watch Aneroids 

Watkin s 

Watkin s Service Pattern Clinometer 

Window Thermometers 

Wye Levels 

Yacht Log 

Zeiss Binoculars 

Zeiss Telescopes 



36, 



38 
64 
29 

39 
61 
27 

39 
40 
40 
5i 
52 
71 
36 
39 
60 

44 
46 

12 
7 

49 
40 

4 1 
10 

47 
47 
46 

15 
75 
77 
36 
76 

75 

71 

7 

5 

56 
64 
59 
5i 

74 
59 
4 1 
4i 
38 
48 
50 
26 
64 

21 
38 

75 
75 



LONDON, YORK AND CAPE TOWN.