heptameride

plural heptamerides · alternative eptameride

1. A thing having seven parts or divisions.

   The Greeks had Seven Wise Men and Seven Sleepers, and the Pythagoreans saw magic in all the heptamerides.

   1914, The Saturday Evening Post, volume 186, number 4, page 45

2. datedchemistryA seven-unit oligomer.

   1938, Albert Ernest Dunstan, Benjamin Talbott Brooks (eds), The Science of Petroleum, vol. 4, page 2830, OCLC 313182716. Fractionation of the liquid polymers gave compounds up to the heptameride.

   2 more examples

   1930, British Chemical Abstracts: Part A, Pure Chemistry, page 317, ISSN 0365-9259. The residue remaining after the separation of the heptameride is colourless and very viscous; there appears little prospect of isolating higher polymerides …

   1939, British Chemical Abstracts: Part A, Pure Chemistry, page 602, ISSN 0365-9259. From available v.d. data the existence of polymerides is shown and the relative amounts of various associated forms up to the heptameride have been calc.

3. obsoleteentertainmentAn interval of pitch equal to 1/7 of a meride, or 1/301 of an octave.

   As 301 = 7 × 43, he called each degree a heptameride, which he made = .03987 of an (equal) Semitone.

   2007, Translator's notes in: Hermann von Helmholtz, On the Sensations of Tone, →ISBN, page 437

   2 more examples

   Sauveur divided the heptameride into two demi-heptamerides. One demi-heptameride is 1/602 of an octave, with frequency ratio 1:2^(1/602) = 1.001 154 or 1.993 cents, very nearly 1/12 of a ditonic comma.

   1984, Joseph Sauveur (trans. Rudolf Rasch), Collected Writings on Musical Acoustics: (Paris 1700-1713), →ISBN, page 28

   Sauveur stresses that the difference between the pure 5th (176 heptamerides) and the tempered 5th (175) is equal to 1: so the temperaments of all the other intervals will also be multiples of 1:

   2008, Patrizio Barbieri, Enharmonic: Instruments and Music 1470-1900, →ISBN, page 378