General Orders

The wind components and atmospheric percentage will be recorded and sent to the
plotting room of guns (but not to that of mortars) before the piece is pointed-wind
components before every shot, atmospheric percentage before the first shot and not
thereafter, unless some material change takes place therein.

If a central station is used for meteorological observation, the wind velocity and
azimuth and the atmospheric percentage will be recorded and sent to the plotting
room before the first shot, but need not be repeated unless there is some material
change therein.

The observer will date, sign, and deliver his report to the officer in charge of the
practice immediately on closing station for the day. Any one of Form 31 b delivered
will contain data pertaining to one company only.

This form will be filed with the Form 31 to which it relates.

This form will be used in connection with such special instrument as provided for observing lateral deviations.

With the instrument set at zero, follow the target by means of the
limb tangent screw, keeping vertical hair on target until the instant
the shot strikes. Then, immediately, by means of the vernier tan-
gents crew, cover the point of fall with vertical hair-the reading of
the instrument will then indicate the amount of apparent angular
lateral deviation.

The observer will date, sign, and deliver his report to the officer
in charge of the practice immediately on closing station for the day.
Any one of Form 31 e delivered will contain data pertaining to one
company only.

This report will be filed with the Form 31 to which it pertains.

NOTE. When instrument is to right or left of gun

1. For all practical purposes, when this distance is small as com-
pared to the range, reduction to the line of fire is not necessary; the
deviation will be reduced to yards from the angles as read, without
reduction, the error being negligible.

2. If distance to right or left be great, or if it is desired to reduce to the line of fire, the following formula may be used:

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This form will be used by the range party observer for recording longitudinal deviations.

The observer will date, sign, and deliver his report to the officer in charge of the practice as soon as practicable after the return of the boat for the day. Any of Form 31 d delivered will contain data relating to one company only.

This report will be filed with the Form 31 to which it relates.

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