( '75 ) 
with one finger on the harpfichord, begin- 
ning with A, and touch none of the fhort 
keys, you will find, after a few repetitions, 
not only that the ear will bear it; but, that 
there is a mildnefs, a fwavity, in the effect 
when contrafted with the firft modus. I fay 
modus, for they are the fame diatonic fcale, 
confifting of the fame number of femitones. 
It is called the Diatonic fcale to diftinguifli 
it from the Chromatic, which afcends and 
defcends by half tones, and which being 
artfully mixed with the other, produces the 
various modulations in modern compofiti- 
ons. The ancients, we are told had other 
fcales, in which their tones were more mi- 
nutely fubdivided. Our fcience of Mufic 
requires no fuch fubtilties. 
The firft of thefe modes is \hefiarp, or 
major, the fecond, thzjlaf, or minor key; for 
there are no more than two keys, or, more 
properly, modes ; and thefe, be the funda- 
mental, or key-note, what it may, are al- 
ways determined by the third being flat or 
Jharp; or, in other words, by the interval of 
half a tone lying between the fecond and 
third, or between the third and fourth note 
of the fcale. There is one thing more to 
be obferved of thisfaf key, namely, that if 
you 
