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# Title: [Johannis Wallis S. T. D. Geometriae Professoris Saviliani, in Celeberrima Academia Oxoniensi, De Algebra Tractatus; Historicus & Practicus. Anno 1685 Anglice editus; Nunc Auctus Latine. Cum variis Appendicibus; Partim prius editis Anglice, Partim nunc primum editis] Johannis Wallis S. T. D. Geometriæ Professoris Saviliani, in Celeberrima Academia Oxoniensi, De Algebra Tractatus; Historicus & Practicus. Anno 1685 Anglice editus; Nunc Auctus Latine. Cum variis Appendicibus; Partim prius editis Anglice, Partim nunc primum editis (shelfmarks Leibn. Marg. 100:1/2, Stück 2; Leibn. Marg. 100:1/2)
# Folio 398, page id 851708439:0422
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L C
 E. B R
idt . LLC.V
que de DD. Deviono e Raphiono hactenus.
hie ea repetere quae hac de re dudum lesipserim ad Clarissimum Virum D. FTenri
cum Older. Uu Regalis Societatis Londini Secretarium; ab ipso cdica in P bi-
losophicis Transactionibus pro Mense Martio 1672.
Abes hic (Clarissime Vir) eorum summam (Ptrictim traditam) quae Fu-
tius seripleram, meas de l’ancenttous Methodos spectantia; duas poristi.
mum quibus praesertim utor; alcetam in Speciebus, alceram in Lineis; u
Exposica Curra Aa (puta Parabola Fie. E) quam in a
tansat a F, Mlametro V D A occurrens in F; ordinacim
eplicentur a V, e DO P currae in O ee tangenti in I
DeCurrenS. P’onatur aurem V a =B
Y A = v, V L =
=an adCOqueD A = - V = a, DF
s
propler similia crians ula) V F. D L:: Y a. D T.
liem, si rangens sit ulira curram, D P = DO; si ci
Era DT = DO: Nempe, DT =DO S intelliratIIE D
in V; leau li exIra V, D P vel DO major, prout tangens
est ultra citrare curram. Acque hactenus univerlaliter.
Tum, habita ipsius DO ccaione quae sit expolicae curva accommodaca;
(ruta, in Parabola, proprer AV. AD:: V ag. DOg =  V: DO- B =:
sine debica reductio, (Putau Proptes   b = BY  adleoque  L 25 a + a
f2 v =2f0 a = va 2 = f2V= f a; deleris utrinque aequalibus; hoc
ot, iis omnibus in quibus a non conspicitur; exeterisque per L a diritis:
2fV= v a
Fandem (qui mechodi nuclens est) posiro D in V, (quo sit a = 0, adcoque
craneseant iplius mulcipla omnia) aequatio extibetir  qualicam (pura 2 f v =va
2 fV = f2, adeoque 2V =
Flane (Locis citatis) accommodatam videas Parabolae, EIlips, Cireulore, Hy.
perbola Paraboloidibus omnibus, (quibus et harum Rcciprocas accenseo,) atque
alibi aliis.
Cissoidi l Fis2.) sic accommodes. F. st (per
Cap. 5. pr. 29. de Mocu) Y a = b = 5 = YvB
(Politospro tinu recto in circulo generante,
cujus ractiusr, SIUIS ver (US 2, _2r -v =1
e B- v = 2V,) adeoque (sublticuris v= a
PCo v, de B = a pCOB, d Y: vb+ 2 X a = a2:
(= D0) = (DT
bsta
27
Voh
Ergo (sumptis quadratis, de mulciplican.
do decultarim,) f2 v3 b + 6f2 v3 Ba
(2~t Ba = 4f22 Ba = V3 B = 2f v ha  vB a = 2f 2 ~ Na
+ 41
Cum vero in his (incer alia) de Tansentibus ducendis sermo tactus sie, libet
Methodi duae pro Curvarum Fangentibus.
ramque generali Forma Facile explicabilem.
Priorem adhibeo Con. Sect. prop. 23, 30, 36, 46, 43, et pastim alibi. Oux haec cst.
F
2vB a =