( 9^7 ) 
Suptt rtciA A G tAn" 
quAm AXCy ex fun^o A con- 
ftrucris Curvis quotcm^ttc 
qualis ejl A B D , ejiis 
nature ut rAdtus cfculi ex 
fingulis (ingularum CurvArum 
punHis B edu6lus B O ^ece- 
tur ah axe A G in Q in Da- 
ta fefnper confianti rat tone : 
ut ncmpe fit ^ Q ad ^ C nt 
M ad N. Conflruendx jam 
fttfjt Traje^ortA qualis ejl ENF, priores Curvas ABD 
fecantes ad angulos reBot, 
Thus far this Letter. Mr. Leihnitz firfl; propofed the 
general Probleme to M, I'Ahhe Conti in ihefe words; 
Trouver une ligne B C \y,qui 
coupe a angles droits toutes 
ies courhes d' une juite de- 
termine d'nne rneme gcndre\ 
par excmplcy. toutes Us H)- 
perholes A B, A C, A D, qul 
ent le meme fommet & le 
neme centre; ^ celapar une 
<voje generale. And in the ABa Eruditorum for OBo> 
her, i6>i8. />. 4/0, 471. he calls the Curves in this 
determinate Series, Curvas ordinatim datas, & pofttione 
datas, & pofitione ordinatim datas. And by all this, 
the Series of Curves to be cut is given, and nothing 
more is to be found, than the other Series which is 
to cut it at right Angles. But Mr. Leihnitz being 
told that his Probleme was folved, he changed it into 
a new one, of finding both the Series to be cut and 
the other Series which is to cur it. And the.particu- 
Eeeeeee lar 
