960 Mr. le cerf on a new-invented 
would hitch into the three teeth at one and the fame 
time) fuppofed to be in due proportion with a pinion of 
lix, and that afterwards one was to make ufe of the fame 
meafure upon a wheel of 42 teeth, the natural confe- 
quence would be, that this pinion would be by fths, or 
lialf its diameter, too big*- 
§ 13. A. pinion of 'feven, fuppofed to be of a proper 
bignefs, with a wheel of 21 teeth, would according to 
the fame meafure of three full teeth taken upon a wheel 
of 70, be too big by its whole diameter, infomuch, that 
the wheel inftead of 70 teeth ought to have but 63, Sec. 
Though the fuperior angles, that is, the circumference 
of the wheels from 12 to 120, and above ad infinitum , 
relatively to the lize of a pinion given according to our 
rule, are and ought to be invariably, the fame ; the lower 
angles, 
leurs angles embrafleroient tout d’un tems Ies trois dents) que l’on fup- 
pofe en jufte rapport avec un pignon de iix, et que Ton vouluffe faire ufage de la 
meme mefure fur une roue de 42 dents, il en refulteroit evidemment que ce pig- 
non fe trouveroit de foit dela moitie de fon diametre trop gros. 
§ 13. Un pignon de fept qui feroit par fuppolition de jufte grolfeur avec une 
roue de 21 dents fe trouveroit, felon la meme mefure de trois dents pleines, 
prifes fur une roue tie 70 trop gros de fon diametre entier, de forte que la 
roue au lieu de 70 dents n’en devroit avoir que 63, &c. Non obftant que Ies 
angles fuperieurs, foit la circonference des roues depuis 12 .a 120 et au delfus 
jufques a l’iniini; relativenrent a lagroffeur d’un pignon donne fejon notre regie, 
6 foient 
