This tip was found in “The Way of the Woods: A Manual for Sportsmen in Northeastern United States and Canada,” by Edward Breck, 1908. I have been trying it out all week and it seems to work. Let me know your experience with it. It works differently depending on whether you are in the northern or southern hemispheres.
The Watch as a Compass
Point the hour-hand to the sun and south will be half-way between the hour-hand and the figure XII.
The compass as a watch
An additional reference was found in “The Compass. A Monthly Journal for Engineers, Surveyors, Architects, Draughtsmen, and Students,” edited by William Cox, 1891-1892.
Many Journals have recently given points about telling the direction by means of a watch. As the watch serves for the compass, so the compass can serve for a watch. The sun is east at 6 a.m., south at noon, west at 6 p.m., therefore, if we consider the semi-circumference of the compass dial E. S. W., we shall find that E. corresponds to 6 a.m., S. to noon, and W. to 6 p.m. Let us figure from S. to W: (S) 12, 1, 2, 3, 4, 5, 6 (W.), and from S. to E. : (S.) 12, 11, 10, 9, 8, 7, 6 (E.). Therefore, to find the time, it is sufficient to direct the compass so as to bring the S. on the figure 12, and to read the figure on which, if it is 3 p.m., the line of sight will pass by the figure 3, the sun being at S.W. at 3 p.m. For greater convenience a vertical stem can be placed above the pivot of the needle.
The direction of the moon may also be found by a similar process. At full moon the earth, the moon and the sun are on one axis, and the positions of the sun and moon with respect to the earth differ by 12 hours. The moon is therefore seen at 1 hour after midnight where the sun is seen 1 hour after noon. In her first quarter the moon lags 6 hours behind the sun. She is visible at midnight where the sun shone at 6 in the evening, that is to say, in the west. In her last quarter the moon is 6 hours in advance of the sun, and is seen at midnight where the sun will shine at 6 in the morning, that is to say, in the east. In order to tell the “quarter” of the moon, remember that she is a deceiver, and that when her crescent is turned like a D, she is not departing, but coming, that is, she is in her first quarter; whereas, when she is turned like a C, she is departing, not coming, or in other words, is in her last quarter. — The Optician, London, England.