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Machine transcription
( 2 )
waist-belt on the left side, and the reels (of cords)
have spring clips by which they can be attached
to the waist-belts on the right side.
8.—By means of the telescope A, the observer views the
distant object direct through the opening B and the ivory
strip on the instrument of the other observer (by double re-
flection) through the opening C. The flap F with the
ivory strip attached being raised (Vide Fig. I.)
9.—"The left" Mekometer or "No. 2's" instrument is
simply an improved form of an optical square and can obtain
exact coincidence with the ivory strip of "No. 1's" instru-
ment and the distant object by moving forwards and back-
wards.
10.—When "No. 2" has obtained coincidence between
the distant object and the ivory strip of "No. 1's" instru-
ment, then No. 1 can also obtain exact coincidence between
the distant object and "No. 2's" instrument by revolving
the drum D. The range (or the distance in yards) is then
read directly off the drum D opposite index E. (Vide
Fig. I.)
General directions for taking any range.
11.—In order to take the range, the observers take
their instruments out of their cases, screw in the handles,
fix telescopes, and raise the flaps.
12.—When the words "right" and "left" are used to
indicate the object to be observed, they will be understood
to mean the object which lies to the right or left front of
the observer.
13.—No. 1 has then to make No. 2 clearly understand
the following :—
1st.—The exact part of the distant object that he is
to get his coincidence upon, whether moving or
otherwise.
2ndly.—The length of the base to be utilised, which
is generally taken at its full length, 25 yards, and
at others by half or double their lengths called
"Half-bases" and "Double-bases" respectively.
14.—Nos. 1 and 2 will now hook together the catches
at the ends of their cords and face the distant object (No. 1
on the right side of No. 2). In this manner they should
both turn outwards and double about 9 paces each for a
25 yard base, taking care to keep the distant object conti-
Roughly two thirds of characters agree with a modern printed edition of the same text. Much of the disagreement is editorial, not misreading. Treat the transcription as a finding aid and read the page image before quoting. How this was measured.