70 NATURAL HISTORY. 



vour to raise or fall his voice, still by half-notes, like 

 the stops of a lute ; or by whole notes alone without 

 halfs, as far as an eighth ; he will not be able to 

 frame his voice unto it. Which sheweth, that after 

 every three whole notes, nature requireth, for all 

 harmonical use, one half-note to be interposed. 



106. It is to be considered, that whatsoever 

 virtue is in numbers, for conducing to consent of 

 notes, is rather to be ascribed to the ante-number, 

 than to the entire number ; as namely, that the 

 sound returneth after six or after twelve ; so that 

 the seventh or the thirteenth is not the matter, 

 but the sixth or the twelfth ; and the seventh and 

 the thirteenth are but the limits and boundaries of 

 the return. 



107. The concords in music which are perfect 

 or semiperfect, between the unison and the diapason, 

 are the fifth, which is the most perfect ; the third 

 next ; and the sixth, which is more harsh : and, as 

 the ancients esteemed, and so do myself and some 

 other yet, the fourth which they call diatessaron. 

 As for the tenth, twelfth, thirteenth, and so in &quot; in- 

 finitum,&quot; they be but recurrences of the former, 

 viz. of the third, the fifth, and the sixth ; being an 

 eighth respectively from them. 



108. For discords, the second and the seventh 

 are of all others the most odious in harmony, to the 

 sense ; whereof the one is next above the unison, the 

 other next under the diapason : which may shew 

 that harmony requireth a competent distance of notes. 



