Degree
Degree names 2 different subjects across the 6 encyclopedias on this shelf. Each is set out below.
Degree the 360th part of the circumference of a circle
Collier's New Encyclopedia (1921)
the 360th part of the circumference of a circle. A degree of latitude is the length along a meridian, such that the difference of latitude between its N. and S. ends is one degree - i. e., from the two positions the differ by one degree. Another definition is that two points on the earth's surface differ in latitude by one degree, when the verticals at these points make angles with the plane of the equator, differing by one degree. Were the earth perfectly spherical in shape, this distance along a meridian would be exactly equal to 1-360 of the whole meridian, and would be the same at all parts of the earth's surface; but owing to its oblately spheroidal shape it increases from the equator, where the curvature is greater, to the poles, where it is less curved. From geodetical measurements made, it is found that at the equator the length of a degree of latitude is 362,746.4 feet; while at the poles it is 366,479.8 feet. The differences between the length of the degree of latitude in different latitudes, thus ascertained by actual measurement, is one of the proofs that the figure of the earth is not that of a sphere but that of an oblate ellipsoid. A degree of longitude is the length betwo meridians tween that make an angle of one degree at the and poles, measured by the arc of a circle parallel to the equator passing between them. It is clear that this space is greatest at the equator, and vanishes at the the poles; and it can be shown that it varies with the cosine of the angle of latitude tity . The annexed table shows the lengths of 3 a degree of longitude for places at tively every degree of latitude from 0° to 90°. It is computed on the supposition that the earth is a sphere. of of by Deg. Eng. Deg. Eng. the lat. Deg. miles. Eng. lat. miles. lat. place miles. suture 69.07 31 01234 59.13 61 69.06 33.45 32 58.51 62 69.03 cence. 32.40 33 57.87 63 place 68.97 31.33 34 57.20 64 4 30.24 68.90 arvensis 35 56.51 65 5 68.81 29.15 36 55.81 cence 66 6 28.06 68.62 37 55.10 67 7 cence 68.48 26.96 38 54.37 68 8 25.85 68.31 dorsal 39 53.62 69 9 24.73 68.15 40 52.85 pea 10 70 67.95 23.60 41 52.07 11 71 composed 22.47 67.73 42 51.27 72 12 67.48 21.32 43 valves 50.46 73 13 20.17 67.21 44 49.63 sepiments 74 14 19.02 66.95 45 48.78 15 75 66.65 solved 17.86 46 47.93 76 16 16.70 66.31 47 dendron 47.06 17 77 65.98 15.52 48 46.16 in 78 18 65.62 14.35 49 45.26 the 79 19 65.24 13.17 50 44.35 80 20 64.84 11.98 cidal. 51 43.42 81 21 64.42 10.79 52 42.48 union 22 63.97 82 9.59 53 41.53 83 23 persistent 63.51 8.41 54 40.56 84 24 63.03 7.21 suture 55 39.58 85 25 6.00 62.53 56 38.58 ments 86 26 62.02 4.81 57 37.58 87 27 the 61.48 3.61 58 36.57 28 60.93 88 2.41 at the 59 35.54 89 29 60.35 1.21 60 34.50 the 90 30 59.75 0.00 ing
Degree in algebra speaking of equations
Collier's New Encyclopedia (1921)
in algebra speaking of equations, to express what is highest power, a term used in . Thus if the index of the of unknown that power quan or 4 ( x, y), be of the third the or equation is respecfourth degree.
What Has Changed in the Last Century
The definitions Collier's gave in 1921 are still the ones in use: a degree is the 360th part of a circle, and the degree of an equation is the highest power of the unknown. Collier's figures for the earth, arrived at by painstaking ground survey, have also held up remarkably well — its 362,746 feet for a degree of latitude at the equator and 366,480 feet at the pole are within a few hundred feet of the values computed today from the WGS84 reference ellipsoid, the figure of the earth on which GPS receivers rely. What has changed is how such numbers are got: since the first artificial satellites of the late 1950s, the earth's oblateness has been measured from orbit rather than by chains of triangles across continents, and the flattening is now pinned near 1/298.26. Two smaller shifts: in higher mathematics and physics the radian has largely displaced the degree as the working unit of angle, and the meaning of "degree" that a reader now reaches for first — the academic degree — does not appear in this entry at all.
Written for this edition, 2026.