General Information

Serial #

N/A

Part Number

2

Total Parts

2

AKA

N/A

Patents

N/A

General Description

Wood, leather, brass.

Dimensions

Note: These reflect the general size for storage and are not necessarily representative of the object's true dimensions.

Length

24.7 cm

Width

26.0 cm

Height

17.2 cm

Thickness

N/A

Weight

N/A

Diameter

N/A

Volume

N/A

Lexicon

Group

Exploration and Survey

Category

Measurement-direction

Sub-Category

N/A

Manufacturer

AKA

White

Country

Scotland

State/Province

Unknown

City

Glasgow

Context

Country

Unknown

State/Province

Unknown

Period

Unknown

Canada

Unknown

Function

Unknown

Technical

Unknown

Area Notes

Unknown

Details

Markings

Tag attached to wooden box reads: 'Article No 148/ Azimuth Mirror/ Kelvin # 5660/ Hydrographic/ Condition - good' White sticker with red border adhered to box reads: 'AZIMUTH MIRROR H.S.No./ Desc . Brass about 7"/ Maker; Kelvin No.5660/ Condition; Fair, Centre pins missing/ Bubble evaporated' Instructions adhered to the inside of the box door reads: 'INSTRUCTIONS FOR THE USE OF LORD KELVIN'S AZIMUTH MIRROR.// BEARINGS can be taken with this instrument in two/ ways. (1) By looking direct at the object over the top of/ the prism. The degrees of the card reflected in the prism/ are then seen close below the object ; (2) By looking through/ the lens at the degree of the card. The first method is applicable/ to objects on the horizon, and is more particularly useful/ for taking bearings of distant landmarks which are too indis-/ tinct to be seen when reflected in the prism. The second/ method may be used either for taking bearings of objects/ on the horizon or for taking bearings of the sun, moon, or/ stars.// For taking bearings by the first method the prism is kept/ turned (arrow-head down) with its mounting stopper against/ the framework. The observer turns the instrument round/ its vertical axis till the prism and lens are fairly opposite/ to the object, and places his eye so as to see the object over/ the prism and reads the bearing of the object from the com-/ pass card as seen reflected in the prism.// For taking bearings by the second method the observer/ looks through the lens at the degree divisions of the com-/ pass card and turns the prism (arrow-head up) round its/ horizontal axis till he brings the image of/ the object to fall/ on the card. He then reads directly on the card the com-/ pass bearing of the object.// The pointer is used merely as an aid in directing the/ instrument towards the object, but the bearing is read directly/ from the object as seen on the compass card. It is not/ necessary the pointer should be pointing exactly towards/ the object unless the altitude be very high For objects/ from horizon up to 38 [symbol for degrees] of altitude the error on the bearing/ would be less than half a degree, even if the pointer were/ pointing 4 [symbol for degrees]/ away from the object.// Makers - KELVIN & JAMES WHITE, Ltd.. 16 to 20 Cambridge Street, Glasgow.'

Missing

N/A

Finish

Unknown

Decoration

N/A