Updated info #2
Aparently the same two dials compass division was used in the US vessels:
Quote:
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The compass card on top of the spider assembly, Figure 34, is clearly visible just below the glass cover of the binnacle. Bearings can be read in tenths and hundredths of a degree. This is made possible by two concentric dials having a 36 to 1 displacement ratio. The entire circumference of the outer dial is divided into ten major divisions to indicate ten degrees of arc so that each major division corresponds to one degree. Each major division is subdivided into tenths, and each tenth is large enough to estimate hundredths. Actual bearings are read against the lubber line fixed on the head. The inner dial carries 36 divisions, each of which represents ten degrees of arc. When the ship makes a complete turn of 360°, the inner dial makes one revolution while the outer dial makes 36 revolutions, or one revolution for every 10° of arc. The speed ratio of the dials is therefore 36 to 1. See sketch on page 28.
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More information here (See pages 27-28):
http://www.hnsa.org/doc/gyromk7/index.htm