C 31’ ] 
properties, might ealily teach them a thoufand cu- 
rious things in geometry, without knowing the theory 
of trigonometry. 
The Chinefe, from time immemorial, knew the 
pafiage of the fun in the ecliptic ; they knew the 
Ears ; they had globes and hemifpheres ; and, by 
means of divers practices and precepts, received from 
their antients, without any great knowlege of fpheri- 
cal trigonometry, might be able upon the globe itfelf 
to refolve many problems. We ought to conclude, 
that our antients were polTeffed of feveral kinds of 
knowlege, received from the patriarchs, and tranf- 
mitted to the Chinefe. Without thefe kinds of know- 
lege, and thefe traditions, by mere obfervations alone, 
the Chinefe could not perform what they did at 
frff. They never well underftood the Nations and 
retrogre (lions of the planets. Reflections upon the 
eclipfes of the fun and ffars taught them antiently, 
by practice, fomething of the parallaxes of the moon. 
Every thing was almoft forget, about the time of 
TJm chi boam , 240 or 246 years before Chaff. But 
it is evident, that, before that time, the Chinefe muft 
have known fomething of the calculations of the 
eclipfes of the moon and fun, and offome equations 
for reducing the mean motion to the true, and for 
calculating the iblffices. 
Mengtf'e , a claffical author, who wrote before the 
burning of their books, mentions clearly enough part, 
at leaft, of what I fay. They certainly knew indif- 
ferently well the proper motion of the fix’d ffars 5 
which was afterwards forgot, for want of examining 
what was extant written in many books. 
I fir all 
