Rappel de votre demande:


Format de téléchargement: : Texte

Vues 471 à 471 sur 679

Nombre de pages: 1

Notice complète:

Titre : Oeuvres complètes de Christiaan Huygens. Correspondance [de Christiaan Huygens], 1666-1669 / publ. par la Société hollandaise des sciences

Auteur : Huygens, Christiaan (1629-1695). Auteur du texte

Éditeur : M. Nijhoff (La Haye)

Date d'édition : 1888-1950

Contributeur : Koninklijke Hollandsche maatschappij der wetenschappen. Éditeur scientifique

Sujet : Huygens, Christiaan (1629-1695) -- Contribution aux mathématiques

Sujet : Huygens, Christiaan (1629-1695)

Notice d'ensemble : http://catalogue.bnf.fr/ark:/12148/cb38949978f

Type : monographie imprimée

Langue : latin

Langue : français

Langue : néerlandais

Format : 23 vol. : ill. ; 29 cm

Description : Correspondance

Description : Autobiographie

Droits : Consultable en ligne

Droits : Public domain

Identifiant : ark:/12148/bpt6k778547

Source : Bibliothèque nationale de France, département Philosophie, histoire, sciences de l'homme, 4-R-788 (6)

Conservation numérique : Bibliothèque nationale de France

Date de mise en ligne : 15/10/2007

Le texte affiché peut comporter un certain nombre d'erreurs. En effet, le mode texte de ce document a été généré de façon automatique par un programme de reconnaissance optique de caractères (OCR). Le taux de reconnaissance estimé pour ce document est de 87%.


being betwixt thé ?Yo~<~ you have it ju<t in the Zenith. For élfe the Sun being near thé Meridian, remains for fome time without any fenfible alteration of its Altitude. Whereibre, though the Meridian Altitude may ferve we!! enough for knowing thé Latitude or the Hight of the Pole upon occafion; yet it will not ferve fbr'nnding precitèly the Z.o~~<* ofthat place. Much lefs are you to rely upon the Sea-compafes, thereby to find the precife time of Noon. Neither are the Aftronomical Rings or other forts of Sundyals fure enough for f hewing the tinte to wwM~ and feconds. But it is better to obferve the Suns Altitude, when 't is in the 2~/? or ~/?, (the nearer, the better:) for being there, its Attitude changes in a fhort time more fenfibly than before or after; and thus from the Hight of the Pole and the Declination o/ Sun the Hour may be calculated; the manner whereof is fuHicientty taught by others; yet by reafon that this Calculation is fomcwhat troublefome, and that alfo there may be fome Errors in the taking of the Suns Altitude, here follows an eaiter way.

8.

~/<w 0~g /Ac Rifing and Setting of the Sun, and the r/wc the ~?/c~, Lo/;g~M~ Sea M/~y be found.

This way doth neither require the Knowledge ofthe Higlat o/~ Pole, nor of the Declination o/~ Sun, nor the Ufe of any ~ro/?ow/M/7i~/?/w/Netther can the Réfractions of the Sun or Stars caufe any confiderable Error, thé refra~ton of thé Morning differing but little or nothing from that of the Eveililig of one and the famé day, efpecially at Sea. Thus then you are to proceed; At thé Rifing and Setting of the Sun, when it is half above thé Horifon, marke thé time of the day, which the Watches then fhew and though you have in the mean time fayl'd on, it is not confiderable. Then reckon by the Watches, what time is e!apPd between them, and add the half thercof to thé time of thé Rifing, and you fhall have the time by the Watches, when theSunwasatSouth.towhich is to be added the Acquation of the prêtent day by the Table. And ifthis togcther makes ta. hours, then was the fhip at Noon under the rame Meridian, where thé Watches werc fet with thé Sun. But if thé (umme be more then 12, then was fhe at Noon under a more ~/?~ Meridian: and if!e(s,then under a worc ~?~, and that by as many times 15. degrees, as that Summecxcecds or cornes fhort hours of ta: as the Calculation thereofhath been already deliver'd. Suppo<e, e. g. that the Watches A and B, as before, were fet with thé Sun at thé place whence you parted, the 20th of .P< and thé 7/v~ fet to thé Hour, min. and féconds, fhcwcd by thé Sun, abating thé Acquation of thaï day, t'/x. 2. min. and 20. ieconds; thé Watch A. being rcduc'd to thé right