Overview Level of Folio 129 r


Size Height 302 mm, width 206 mm.
Watermark No watermark could be identified by the project group. Drake's identification: Watermark type 15. Drake's description: Thick crossbow 34 X 35mm. Date of earliest letter with this watermark is May 1608.
Comments Written by Galileo; contains drawings, texts. Relation to the Discorsi: work on 2/36-th-22.
Folio 129 r (final text)
1 Sit bd media inter sd, dc, et centro d, intervallo b, secetur de, et per b ipsi st parallela bia.
2 Quia ts tangit, et tc secat, et ba est parallela ts, erit [triangulum] ati similis [tri]angulo tcd.
3 Credo angulum sec bifariam esse sectum per eb.
4 Angulus tds duabus circumferentiis oc, ct insistit; ergo illae sunt similes, et circumferentia do similis est dct; ergo ut linea do ad oc, ita dt ad tc: et quia [rectangulum] dsc aequatur [quadrato] st, ergo ut ds ad st, ita ts ad sc: ergo [triangul]a dst, tsc similia sunt, quibus et [triangula] odc, icb similia sunt.
5 Quia est ut sd ad de, ita de ad dc, ergo [triangulum] sde similis est [triangul]o dec, et ut se ad ec, ita sd ad de, et ita est sb ad bc: ergo angulus ces bifariam secatur linea eb.
C01 200
134
71
18


Overview Level of Folio 129 r