The delivery voyage of the tug-boat Plutao, featured in the October 2017 issue of Sea Breezes, was most interesting.

Its author, George Hoyle, mentions that the magnetic compass on board was one of the reflecting projector types installed on the monkey island and with a reflected image of the compass card projected down into the wheelhouse. This sort of binnacle has been around from at least the early 1950s since its installation saved the expense of fitting a separate steering compass. As far as a helmsman was concerned, a stand-alone steering compass was preferable because, even with the projector periscope fully extended, he had to be continuously looking straight ahead so as to read the compass. Not a very comfortable posture for a two hour trick at the wheel. For the duty officer to see the compass, he usually had to ask the man at the wheel to stand aside, although with some models, it was possible to see the image of the compass card from either side of the periscope.

Another short-coming of this sort of binnacle was when one had to take bearings at night, since the instrument doubled for this purpose and was not just for steering by. When taking a bearing of a star for checking the compass error or of shore lights, it was necessary to reduce the illumination of the compass card. This resulted in the reflected image in the wheelhouse also being dimmed and so in next-to-no-time the helmsman would be calling out something like “Second Mate! I can’t see the compass”. In ships not equipped with gyro compasses and steering repeaters, this was a nightly occurrence. Perhaps, with the present day projector binnacles, this design fault has been rectified. Personally, I always preferred the older arrangement in which a separate steering compass was fitted in the wheel-house. Here below is a picture of such a wheel-house.

Staying with the October edition, it is good to see that some old naval customs are being retained, as per “A Naval Tradition” by Roger Paine (Pages 54 and 55). I was puzzled though by the way in which geographic positions were expressed. Namely: Latitude and Longitude in Degrees and Decimal parts of a degree. Instead of in Degrees and Minutes. If, during my time as a shipmaster, I had been told to proceed to a position expressed in such a way then I would have asked for clarification since it would not have been prudent to assume that the decimal parts actually meant minutes of Latitude or Longitude. For instance, the chosen position for the Battle of Trafalgar in the feature, is given as 36.32N- 6.16W (no Degree signs). In customary units, this works out at 36° 19’N- 6° lO’W (rounded to the nearest minute). Changing the decimal parts into minutes is easy enough, although it would be tedious having to do the sums repetitiously. Just picture a tramp-ship Second Mate correcting his ship’s World outfit of charts from a pile of Notices to Mariners containing heaps of positions in decimalised degrees. If this is another modern trend then I’m glad to have retired.

16 Stableford Drive, Pye’s Pa,
Tauranga, Bay of Plenty, 3112
New Zealand
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