Abstract
Jinchi-yoroku (JCYR) _??__??__??__??_, a tablature score for gakuso _??__??_ (the long zither used in gagaku _??__??_), was compiled in the late 12th century by Fujiwara no Moronaga _??__??__??__??_ (1138-92). It stands out among the rich variety of written source materials associated with gagaku as a comparatively large scale source. It includes explanations of notational systems _??__??__??_ and tablature scores of choshi _??__??_, saibara _??__??__??_, togaku _??__??_, komagaku _??__??__??_, and gigaku _??__??_ pieces.
The elements of the notational system of JCYR are as follows:
1. Primary tablature signs indicating names of the strings of the instrument
2. Secondary signs dealing with rhythm
3. Tertiary signs dealing with performance techniques, especially those of the left hand
After analysis focusing on the first two elements, it has become clear that all measured togakv pieces can be classified into four rhythmic types:
Type AA: one primary tablature sign for every kobyoshi _??__??__??_ (unit of rhythm)
Type A: one primary tablature sign for every kobyosh, or one primary tablature sign for even-numbered kobyoshi and two or more primary tablature signs for odd-numbered kobyoshi; the secondary sign ka _??_ appears only in odd-numbered kobyoshi
Type B: two or more primary tablature signs for every kobyoshi, with a syncopated melodic movement; the secondary sign ka appears only in odd-numbered kobyoshi
Type AB: a mixture of Types A and B, with one or two primary tablature signs for each kobyoshi; the secondary sign ka appears both in even-and odd-numbered kobyoshi
In the major part of the togaku repertoire, each measured piece has original melody (genkyoku _??__??_) and an arrangement of this melody (dokyoku _??__??_). Most of the original melodies may be classified into Type A and the arranged ones into Type B.In some cases, melodies of Type B are given the metrical specification gaku-byoshi _??__??__??_, as opposed to tada-byoshi _??__??__??_. Analysis of the frequency of appearance of the secondary sign ka, especially when comparing Types A and B, shows that genkyoku of Type A are likely to bear the indication tada-byoshi, and that this is the same as that of tada-byoshi as interpreted today, in the sense that the odd-numbered kobyoshi are of longer duration than the even-numbered.
