45.--In music which is _not_ part-writing, the transcriber will have to use his discretion as to the repetition of accidentals which have already appeared in another "part" in the same measure. The guiding principle will be to avoid the likelihood of error on the part of a competent reader.
46.--Care must be taken to turn the stems of half notes and shorter notes according to the principles of short score, and not necessarily as they are in the open score.
47.--Co-relatively, in transcribing from short score to open, it will occasionally be necessary to put accidentals in the latter which are not in the former. The commonest form of this is probably in extracting a single part, soprano, alto, tenor, or bass, from an ordinary short score hymn or chant book, and writing it in a part-book for the particular voice. Thus, in transcribing the tenor of the following extract from the hymn-tune "Heathlands" into a part-book, it would be necessary to insert a natural before the A.
48.--Far more often, however, it is necessary to _omit_ naturals used to contradict an accidental occurring in a part which is not being copied. Thus, in the following extract from the tune "Endless Alleluia," the natural in both the tenor and bass would be unnecessary were these parts written out separately from the other parts and each other.
(The A sharp in the tenor of this extract suggests C sharp so strongly apart from the rest of the harmony, that the natural is almost a necessity even had the previous treble C sharp not been included. Not being required according to rule, however, it should be enclosed in brackets--a not infrequent, and very commendable, device with careful writers, when an accidental is desirable but not necessary according to rule.)
49.--The stems, of course, must be turned up or down according to their position above or below the middle line, and not as in the short score.
50.--In copying out a single part from a score, full or short, care must be taken in abbreviating a number of measures' rest. The usual way of doing this is to write the number of measures over a single measure, thus:
But if a pause occurs in any of the other parts of the score this will not do. The number of bars before the pause must be counted, and the pause--or pauses--shown in the abbreviation as follows, assuming it to occur in the thirteenth bar: