Fred_BRumata,
Can you explain what that means?
Thanks,
Fred
I think what he means, Fred, is that if you take a compass rose and make (for example) the radius one degree at the equator, then draw a diagonal (hypotenuse) to any degree up from 90 (say 45 degrees) from the rose center to the circumference edge, and then draw a vertical line down from that point to the 90 horizontal line where it and the line you just drew (side opposite) form a right triangle, the line length along the side adjacent (90 degree line) then represents the scale of longitude (one degree) at 45 degrees north or south latitude on the globe.... For me it is more entertaining to use this method to scale longitude than to use the curved lat/long scale associated with all printed work sheets where the scale is drawn for you. You may then also take any length in minutes (and seconds if the scale is sufficiently large) . I did my best... :)
I always assumed that if a measurement in nautical miles or knots (say boat speed) is required, I use full knots as measured along any great circle line of longitude irregardless of latitude; but if a measurement is called for in degrees, minutes, and seconds (such as in the trig) I then use the method described above to ascertain the length of degrees of longitude at higher latitudes. I hope this made sense.
joe
Can you explain what that means?
Thanks,
Fred
I think what he means, Fred, is that if you take a compass rose and make (for example) the radius one degree at the equator, then draw a diagonal (hypotenuse) to any degree up from 90 (say 45 degrees) from the rose center to the circumference edge, and then draw a vertical line down from that point to the 90 horizontal line where it and the line you just drew (side opposite) form a right triangle, the line length along the side adjacent (90 degree line) then represents the scale of longitude (one degree) at 45 degrees north or south latitude on the globe.... For me it is more entertaining to use this method to scale longitude than to use the curved lat/long scale associated with all printed work sheets where the scale is drawn for you. You may then also take any length in minutes (and seconds if the scale is sufficiently large) . I did my best... :)
I always assumed that if a measurement in nautical miles or knots (say boat speed) is required, I use full knots as measured along any great circle line of longitude irregardless of latitude; but if a measurement is called for in degrees, minutes, and seconds (such as in the trig) I then use the method described above to ascertain the length of degrees of longitude at higher latitudes. I hope this made sense.
joe