Pamphlet on the Turret Dreyer Table
as Fitted in the Turrets of H.M. Battleships,
and in the Transmitting Stations of Certain Cruisers
This typewritten pamphlet offers specific detail on the small Dreyer table developed for ships unable to accomodate a proper Dreyer table, or where a backup capability was required in case of damage. It was apparently one of at least 4 pamphlets comprising the "Guard Book for Pamphlets on Dreyer Tables". Its late date of publication may indicate that this equipment enjoyed an extended life in some cases, or that they were making up for a lack of proper documentation back in the heyday.
My copy is a black-and-white photocopy generously provided me by Bill Schleihauf.
The pamphlet is concise but packed with information on the device and its components and operational limits.
I get the sense that, at the time of the writing of the pamphlet, that this table was really only used in cruisers.
The table was pattern number 6880.
The table was designed for battleships for the local control of 1-2 turrets as a backup to the TS or in cases where fire was to be split.
The intent was that the rangefinder mounted in the turret would supply the range information.
It was also used in light cruisers, in their Transmitting Stations, where presumably the full Dreyer tables could not fit.
The table had an electric drive, but had a hand backup. Sometimes the electric drive was removed.
from p. 4 -- a list of cruisers fitted with the table in their Transmitting Stations:
Calliope, Centaur, Cardiff, Cambrian, Concord, Ceres, Canterbury, Coventry, Castor, Caledon, Curacoa, Champion, Calypso, Curlew, Constance, Caradoc, Carysfort, Cleopatra, Comus, Conquest, Brisbane, and Dartmouth.
The basic configuration of this table is that it resembled the functionality of the Dreyer Mark III, but without a Bearing Plot or Dumaresq.
The text alludes to the fact that people added equipment to these tables almost as they saw fit: master range transmitter, P.I.L gear (Position in Line ... equipment to permit the ship to group its fire with that of a lead ship in the squadron), and a mean range transmitter.
When used in turrets, there was occasionally an automatic range plotting mechanism in which the RF drove a pricker on a worm screw under the paper via flexible shafting. It was sometimes disconnected, and light cruisers could not use this as they often plotted from 3-4 RFs. Plotting other than the automated pricker was done by hand... perhaps by a pencil dot.