Volume 1

The sector on a quadrant, or, a treatise containing the description and use of four several quadrants; two small ones and two great ones, each rendred many wayes, both general and particular. Each of them accomodated for dyalling; for the resolving of all proportions instrumentally; and for the ready finding the hour and azimuth universally in the equal limbe. Of great use to seamen and practioners in the mathematicks / Written by John Collins accountant philomath. Also an appendix touching reflected dyalling [by J. Lyon] From a glass placed at any reclination.

  • Collins, John, 1625-1683.
Date:
1659
Catalogue details

Licence: Public Domain Mark

Credit: The sector on a quadrant, or, a treatise containing the description and use of four several quadrants; two small ones and two great ones, each rendred many wayes, both general and particular. Each of them accomodated for dyalling; for the resolving of all proportions instrumentally; and for the ready finding the hour and azimuth universally in the equal limbe. Of great use to seamen and practioners in the mathematicks / Written by John Collins accountant philomath. Also an appendix touching reflected dyalling [by J. Lyon] From a glass placed at any reclination. Source: Wellcome Collection.

    329/412 (page 13)
    ’• OftheS^tuB. , Ex^itmfh the ycarc Id^o,^3Vl^g fosmdtirtt tlie SiH day .Iwpned upon a Tjb«r/<£«J7,looksin.ro the ccfomn againil Jitnc y and Fehuarj y you 'A’ill itiid chat the jthy i ^ch, 21 xh and 28th daycs of thofe Monalis-were TbmJdayeSy whence it might be concluded if need were that the quarter day or day of chat y eare hapneth on the Lords iay^ Of ths THe £paB is a ntioi^er carried on in account from ye'arc to yeare towards a new change , and is 11 dayes, and feme odde time belides, caufedby realon of the Moons motion, which ebangeth 12 times in a yeare Sokr 3 and runnes alio this 11 d'ayes more towards a new change 5 the ufe of it ferves to find the' Moones age 5 and thereby the time of high Water.- To J^newthe JiToons age* ■ Dde tonhe day ofthe Moneth the fp^^^jand fo many days more, as are moneths from tJMarch to the moneth you are in, including both moneths , thefumme (if leffe then 50) is the Moones age, ifmore,fubtrad 30, and the refidue in the Moons* { props vernm*) Example* The EpaBFox the year idyS'is 5,and let it be required to know the Moons age the 28 of being the fife moneth from March both inclufivc 6 28 $ ^ The fumme of thefe three numbers is 39 whence rejedling 30, the remainder is 9 for the Moons age Tought. - The former Rule ferves when the Moneth hath 31 ■ dayes, but if the Moneth hath but 30 Day es or leffe, cake away but 29 mad . the refidue is her agef -