Right angle of what a right angle is, namely two straight lines intersecting to form two equal and adjacent angles. The straight lines which form right angles are called perpendicular. Euclid uses right angles in definitions 11 and 12 to define acute angles (those smaller than a right angle) and obtuse angles (those greater than a right angle). Two angles are called complementary if their sum is a right angle. Book 1 Postulate 4 states that all right angles are equal, which allows Euclid to use a right angle as a unit to measure other angles with. Euclid's commentator Proclus gave a
Allied Masonic Degrees equivalent of the Allied Masonic Degrees, nor are the degrees for which it is responsible carried out under the auspices of any of the Scottish masonic bodies, although the 'Red Cross of Babylon' is a truncated version of the Scottish 'Babylonish Pass' degree under the control of the Supreme Grand Royal Arch Chapter of Scotland. There is no reciprocal agreement on intervisitation in the 'Lodge & Council' degrees between the Supreme Grand Royal Arch Chapter of Scotland and the Council of the Allied Masonic Degrees. Nonetheless, "The Grand Council of the Allied Masonic Degrees of England and Wales and Districts