Sunday, July 21, 2019

How to Find Your Way Without A Compass, Part Two, The Watch As A Compass©



Watches, Picture by the author

  
Okay, you forgot to bring a compass with you, you are “misplaced” and you need to orient yourself.  You are using the steps of the Survival Drill to decide if you should stay put or if you should try to walk out (for more on the Survival Drill, see “Survival Drill”, Updated and ExplainedHERE), but first you need to reorient yourself.  You are took an inventory of things in your pack and pockets that could help you, and you realized that you don’t have a compass, but you do have a watch.

No problem, everybody knows, the Sun rises in the east and sets in the west, right?  And, you are wearing a watch and with a watch, you can use the Sun to find north and south, right?  And of course, you know how to use a watch and the Sun to find the direction of north and south, right?  Right?

Well in case you don’t know, here are the answers. 


An excerpt from “The American Architect And Building News”, p. 75


The method of finding the points of the compass with a watch and the Sun was called “orientation by the sun with a watch”1 during the late 19th and early 20th centuries.  “Misplaced” modern adventurers can use either traditional analog watches or today’s modern digital watches, to find the approximate direction, of the points of a compass. 


From Survival: Land, Sea, Jungle, Arctic, p. 42, Fig. 17, picture by the author


There are two methods for finding the north-south line with a watch, one that is used for north of the Tropic of Cancer, in the northern hemisphere, where you will find the general direction of south, and one for use south of the Tropic of Capricorn, that is used to find the general direction of north.

With both methods, it is important that your watch shows Standard Time and not Daylight Saving Time, or the result will be in error by as much as 16 degrees2.  Daylight Saving time is used by many countries in the northern hemisphere, starts in March to April, and ends during September to November; while in the southern hemisphere it starts during September to November and ends during March to April.  If your watch is set for Daylight Savings Time, set it back an hour, so that your watch shows Standard Time.


An excerpt from “Truth”, p. 656


Something else that is important to know, is what I call the “the six in the morning to the six at night rule”.  This rule was noted, but not named, by both the editor of “Truth” and by John Phin, the author of the “How A Watch May Be Used As A Compass”.  This rule states that for all hours between 6 o’clock in the morning and 6 o’clock in the evening, you divide in half the smaller angle between “12” and the hour hand, the angle that is less than 180o.  From 6 o’clock in the evening until sundown, and from sunrise until 6 o’clock in the morning, you bisect the larger angle between “12” and the hour hand, the angle that is greater than 180o. 

If you think about it, in the northern hemisphere, the direction of south sweeps clockwise around the watch dial from around “8” or “9” at sunrise, noon is at “12” and continues to “3” or “4” at sunset.  The opposite is true in the southern hemisphere, with the direction of north sweeping clockwise around the dial and at sunrise, north is opposite “8” or “9”, while at noon the “12” points to north and at sunset north is opposite “3” or “4”.  This important rule is, unfortunately, is missing from most modern books on survival, that teach about using a watch to find the compass points.


Adapted from Survival: Land, Sea, Jungle, Arctic, p. 42, Fig. 17, picture by the author


In the northern hemisphere, north of the Tropic of Cancer, to find the north-south line using a traditional or analog watch, point the hour hand at the sun, while holding the watch in your hand, face up and level.  To make it easier to line up the hour hand with the sun, or if it is cloudy and overcast, hold a twig or a matchstick on the edge of the watch, where the hour hand is pointing, so that it cast a shadow.  Alternatively, for greater accuracy in determining the compass points, drive a stick into the ground, standing straight up, and lay your watch on the ground with the shadow of the stick falling along the hour hand and through the center of the watch.  While holding the watch and the twig level, turn in place so that the shadow is cast along the hour hand through the center of the watch.  Remembering “the six in the morning to the six at night rule”, divide the angle between the “12” and the hour hand in half, drawing an imaginary line from the center of the watch through this halfway point, will give the general direction of south.

Remembering the “the six in the morning to the six at night rule”, if it is four o’clock in the afternoon, and you take half of the smallest angle from “12” and the Sun at “4” the line pointing south will run through “2”.  If it is eight o’clock in the morning, and the “8” is pointing at the Sun, then south is half the smallest angle between “8” and “12”, or “10”.  At noon, since north of the Tropic of Cancer the sun is always south of you, then if the hour hand is pointing at “12”, that is the approximate direction of south.

Using the “the six in the morning to the six at night rule”, if it is 7 o’clock in the evening, in the northern hemisphere, then half of the larger angle from the “7” to the “12”, will be between “4” and “3”, and that will point towards south.  If it is “5” in the morning then half of the larger angle from the “5” to the “12” will be between “8” and “9” and that will point towards south.  At 6 o’clock in the morning south will be opposite “9” and at 6 o’clock in the evening, the “3” will point the direction to south.


This picture was taken on May 26 at 12:48, Daylight Savings time, by the author.


North of the Tropic of Cancer, to use a digital watch to find south, first place an upright stick in the ground to create a shadow.  Then draw a picture of a traditional clock face on the ground, with the stick on the edge of the watch picture, where the hour hand is, so that a shadow is cast through the center of the picture.  Using “the six in the morning to the six at night rule”, divide the angle between “12” and the hour hand in half, and drawing an imaginary line from the center of the picture through the halfway point, this will give you the general direction of south.


Adapted from Survival: Land, Sea, Jungle, Arctic, p. 42, Fig. 17, picture by the author



An excerpt from “How A Watch May Be Used As A Compass”, The Seven Follies of Science, by John Phin, p. 134-135



In the southern hemisphere, south of the Tropic of Capricorn, to find the compass points using a traditional or analog watch, point the number “12” at the sun, while holding the watch in your hand, face up and level.  To make it easier to line up the “12” with the sun, or if it is cloudy and overcast, hold a twig or a matchstick on the edge of the watch at the “12”, so that it cast a shadow.  Or, for greater accuracy in finding the compass points, drive a stick into the ground so that it is standing straight up; lay your watch on the ground so that the shadow of the stick falls along the “12” and through the center of the watch.  While holding the watch and the twig level, turn in place so that the shadow is cast from the “12” through the center of the watch.  Using “the six in the morning to the six at night rule”, divide the angle between the “12” and the hour hand in half, an imaginary line drawn from the center of the watch through this halfway point, gives the approximate direction of north.

Again, using “the six in the morning to the six at night rule”, if it is four o’clock in the afternoon, and you take half of the smallest angle from “12” and the Sun, to “4” the line pointing north will run through “2”.  If it is eight o’clock in the morning, and the “12” is pointing at the Sun, then north is half of the smallest angle between “8” and “12”, or at “10”.  At noon, since south of the Tropic of Capricorn the sun is always north of you, then if both the hour hand and the “12” is pointing at the Sun, then that is the approximate direction of north.

Remembering the “the six in the morning to the six at night rule”, if it is 7 o’clock in the evening, in the southern hemisphere, then half of the largest angle from the “7” to the “12”, will be between “4” and “3”, and that will point towards north.  If it is “5” in the morning then half of the largest angle from the “5” to the “12” will be between “8” and “9” and that will north.  At 6 o’clock in the morning, north will be opposite the “9” and at 6 o’clock in the evening; the “3” will point the direction to north.

South of the Tropic of Capricorn, to use a digital watch to find north, first place an upright stick in the ground to create a shadow.  Then draw a picture of a traditional clock face on the ground, with the stick on the edge of the watch picture, where the “12” is, so that a shadow is cast from the “12” through the center of the picture.  Remembering “the six in the morning to the six at night rule”, divide the angle between “12” and the hour hand in half, and drawing an imaginary line from the center of the picture through the halfway point, will give you the general direction of north.


An excerpt from “Truth”, p. 656


It is important to remember, however, that you can only determine the general direction of north, south, east and west with a watch and the Sun.  As I pointed out in “How to Find Your Way Without a Compass, Part One”, HERE: except on two very special days of the year, you will only be able to find, “A rough approximation to the direction…within about 20 deg.”3.  This should good enough, however, for you to reorient yourself. 

What this all means to the “misplaced” wilderness adventurer is, if you use a watch and the Sun to determine your direction of travel, you will have an error in your heading.  As the “1 in 60” rule of thumb shows, a 1° error in your line of travel over one mile is not much (you will only be off track by about 88 feet or almost 30 yards), however over ten miles, it is much more.  With an error of 20° in your line of travel, you will be off track by a third of mile for every mile you travel.  Over a larger distances, with only a watch and the Sun to orient yourself, you might end up more lost than you were when you started and for this reason, you should always carry at least one, but better yet, two compasses with you when you are in the wilderness.  For more on why having two compasses is important see “Getting Lost And What To Do About It”, Circa 1915” HERE.

For those of you, who would like to understand the science and the history of this method of using a watch as a compass, please see the Appendix below.

For more on “How to Find Your Way Without a Compass, Part Three, Using The Shadow-Tip Method”, check back in following weeks.

I hope that you continue to enjoy The Woodsman’s Journal Online and my videos at BandanaMan Productions. Don’t forget to follow me on The Woodsman’s Journal Online and subscribe to BandanaMan Productions on YouTube, and if you have questions, as always, feel free to leave a comment on either site.


Appendix

One of the questions that I had, when I was researching how to use your watch as a compass was, what is the science behind this method?  Since I had this question, I thought that some of my readers might also be curious, so here is what I found.

On page 656, of “Truth”, written in October 2, 1890, contributor T. A. T. Hallowes explained the science of using a watch as a compass:

An excerpt from “Truth”, p. 656


John Phin, in The Seven Follies of Science, 1906, further explained how the watch as a compass works.


An excerpt from “How A Watch May Be Used As A Compass”, The Seven Follies of Science, by John Phin, p. 134-135


There is good science behind this method, and a watch works as a compass “because of the mathematical relationship between the orbit of the sun and the circle of degrees described by the watch dial4.  The Sun, from 6:00 am when it is in the east, to 6:00 pm when it is in the west, passes through an arc of 180o, which means that it moves 15o an hour over 12 hours.  During this same time, the hour hand on your watch moves 360o or twice as fast as the Sun, and this is why the distance between the “12” and the hour hand is halved.

 
An excerpt from Plane Safety And Survival, p. 75

The other thing that I was curious about since I am a reenactor and an “experimental historian” was, when was using your watch as a compass first written about.  The earliest reference to this method of finding the general direction of north and south, that I could find was reprinted in “Truth” on page 656 and is an excerpt from The Text-book of Military Topography, which was originally published in 1884.  One of the interesting things in this excerpt from Col. W. Richards’s book was his statement that, “This simple expedient is useful on horseback, and it enables one to hold a map with its sides nearly north and south without dismounting.4  The reason that I found this interesting, is that in the Art of Travel, 1872, by Francis Galton, he noted on  on page 287 that “…compasses cannot be used on horseback without stopping…”5.  Compasses during the mid to late 19th century were air filled and from personal experience with using air filled compasses, it would have been very difficult to settle the needle, while riding on a horse; using a “watch as a compass” to orient your map, would have been a clever “wrinkle” or trick.


An excerpt from “Truth”, p. 656


Additionally, a note for reenactors and experimental historians: watches were expensive luxury items during the end of the 18th century and were not commonly carried, except by the wealthy, until the early years of the 19th century.  Therefore, for reenactors of the late 19th century onwards, this would be a period correct skill.  However, for modern reenactors of late 18th and early 19th centuries, who are interested in direction finding and time telling, look for the upcoming article “How To Tell Direction and Time Like Robert Rogers And His Rangers”, coming soon.


Notes

1  Editor, “Truth”, No 718, Vol 28, [Bolt-court, Fleet Street, London, Oct 2, 1890] p 656

2  Risk, Paul, H., Outdoor Safety And Survival, p. 285

3  Editor, “Truth”, No 718, Vol 28, [Bolt-court, Fleet Street, London, Oct 2, 1890] p 656
The degree of inaccuracy appears to be, as much as, 20 degrees, with the authors of Survival: Land Sea, Jungle Arctic, 1944, noting “…you can use a watch to tell true north or south with an error of less than 8 degrees.”  Bradford Angier echoed this in 1971, when he wrote “A watch used as a makeshift compass … can be relied upon to be true within eight degrees”, in How to Stay Alive in the Woods.

4  Ibid., p. 285

5   Francis Galton, Art of Travel, 1872, p. 287


Sources

Airlines War Training Institute, Survival: Land, Sea, Jungle, Arctic, [The Infantry Journal, Washington, D.C., 1944] p. 41-42

Anderson, Eric G., M.D., Plane Safety And Survival, [Aero Publishers, Inc, Fallbrook, CA, 1978] p. 51-63, 75

Angier, Bradford, How to Stay Alive in the Woods, [Orginally published as Living Off The Country: How to Stay Alive in the Woods, Collier Books, New York, NY, 1971] p. 182

Department of the Airforce, Outdoor Survival Skills: How to Survive on Land, Sea and Ice!, [Info Books, Toronto, Canada, 1980] p. 2-86

Craighead, Frank, Jr., Phd, and Craighead, John J., Phd., How to Survive on Land and Sea, [United States Naval Institute, Annapolis, MD, 1956] p. 11

Editor, “The American Architect And Building News”, Vol. XXX, No. 775, [Ticknor & Co Publishers, Boston, MA November 1, 1890] p. 75 https://books.google.com/books?id=HYdMAAAAYAAJ&pg=RA1-PA75&dq=finding+south+with+a+watch&hl=en&sa=X&ved=0ahUKEwiyt5-xjZTjAhUjwFkKHen8Aio4hgMQ6AEIPDAE#v=onepage&q=finding%20south%20with%20a%20watch&f=false, accessed 7/1/19


Galton, Francis, Art of Travel, 1872, [Stackpole Books, Harrisburg, PA, 1971], p. 287

Louis, The Blacksmith and Wheelwright,Vol. XXXVIII, No. [M. T. Richardson Company, New York, NY, July 1898] p. 124

Phin, John, “How A Watch May Be Used As A Compass”, The Seven Follies of Science, [D. Van Nostrand Company, New York, NY 1906] p. 134-135

Risk, Paul, H., Outdoor Safety And Survival, [John Wiley & Sons, New York, NY, 1983] p 284-285

Stevens, E.E., “The Handy Compass”, Labor Digest: A National Magazine for the Advocacy of Industrial Peace, Vol 3, [Minneapolis, MN, December 1910] p. 10-11

Thorsen, Steffen, “Daylight Saving Time – DST – Summer Time”, [timeanddate.com, 2019] https://www.timeanddate.com/time/dst/, accessed 7/1/2019

“Where Do the Sun and Stars Rise?” [Stanford Solar Center, 2005] http://solar-center.stanford.edu/AO/sunrise.html, accessed 9/8/18

Wikipedia Contributors, “1 in 60 rule”, [Wikipedia, The free Encyclopedia, December 21, 2017] https://en.wikipedia.org/wiki/1_in_60_rule, accessed 7/10/19



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