The mariners magazine, or, Sturmy's mathematical and practical arts containing the description and use of the scale of scales, it being a mathematical ruler, that resolves most mathematical conclusions, and likewise the making and use of the crostaff, quadrant, and the quadrat, nocturnals, and other most useful instruments for all artists and navigators : the art of navigation, resolved geometrically, instrumentally, and by calculation, and by that late excellent invention of logarithms, in the three principal kinds of sailing : with new tables of the longitude and latitude of the most eminent places ... : together with a discourse of the practick part of navigation ..., a new way of surveying land ..., the art of gauging all sorts of vessels ..., the art of dialling by a gnomical scale ... : whereunto is annexed, an abridgment of the penalties and forfeitures, by acts of parliaments appointed, relating to the customs and navigation : also a compendium of fortification, both geometrically and instrumentally / by Capt. Samuel Sturmy.

About this Item

Title

Author

Sturmy, Samuel, 1633-1669.

Publication

London :: Printed by E. Cotes for G. Hurlock, W. Fisher, E. Thomas, and D. Page ...,

1669.

Rights/Permissions

To the extent possible under law, the Text Creation Partnership has waived all copyright and related or neighboring rights to this keyboarded and encoded edition of the work described above, according to the terms of the CC0 1.0 Public Domain Dedication ( http://creativecommons.org/publicdomain/zero/1.0/). This waiver does not extend to any page images or other supplementary files associated with this work, which may be protected by copyright or other license restrictions. Please go to http://www.textcreationpartnership.org/ for more information.

This text has been selected for inclusion in the EEBO-TCP: Navigations collection, funded by the National Endowment for the Humanities.

Link to this Item

http://name.umdl.umich.edu/A61915.0001.001

Cite this Item

"The mariners magazine, or, Sturmy's mathematical and practical arts containing the description and use of the scale of scales, it being a mathematical ruler, that resolves most mathematical conclusions, and likewise the making and use of the crostaff, quadrant, and the quadrat, nocturnals, and other most useful instruments for all artists and navigators : the art of navigation, resolved geometrically, instrumentally, and by calculation, and by that late excellent invention of logarithms, in the three principal kinds of sailing : with new tables of the longitude and latitude of the most eminent places ... : together with a discourse of the practick part of navigation ..., a new way of surveying land ..., the art of gauging all sorts of vessels ..., the art of dialling by a gnomical scale ... : whereunto is annexed, an abridgment of the penalties and forfeitures, by acts of parliaments appointed, relating to the customs and navigation : also a compendium of fortification, both geometrically and instrumentally / by Capt. Samuel Sturmy." In the digital collection Early English Books Online 2. https://name.umdl.umich.edu/A61915.0001.001. University of Michigan Library Digital Collections. Accessed June 15, 2024.

Pages

QUEST. III. Two Ships Sail from one Port; The first Ship Sails directly South, the second Ship Sails W. S. W. more than the first by 35 Leagues, and then were asunder 76 Leagues; The Question is, How ma∣ny Leagues each Ship Sailed.

FIrst draw the Meridian-line AB, and from A draw a W. S. W. Course as AC continued, and from C lay down the 35 Leagues unto D. Now draw the Chord-line of 6 Points, as BC; then take 76 Leagues, and lay it from D to cut the Chord-line in E. Lastly, from E you must draw a Parallel Meridian, which will cut the Rhomb-line in F; so measuring EF, you shall have 45 68/100 Leagues, that the first Ship sailed directly South: So the second Ship sailed 35 Leagues more, therefore must Sail in all 80 68/100 Leagues, which is the Distance required.

[illustration] geometrical diagram

By the Artificial Tables of Sines and Numbers.

As the Side ED	76 Leagues co: ar.	811919
To the Sine of the Angle ECD 56 deg. 15 min	991985
So is the Side CD	35 Leagues	154407
To the Sine of the Angle CED 22 deg. 31 min.	958311

which substract from 56 deg: 15 min. you have the Angle at D 33 deg. 44 min.

Then,

As the Sine of the Angle at F 67 deg. 30 min. co. ar.	003438
Is to his opposite Side	ED 76 Leagues add	188081
So the Sine of the Angle at D 33 deg. 45 min. add	974455
To his opposite Side	FE 45 ••8/100 Leagues	165974

So the South Ship Sailed 45 68/100 Leagues; and the other W. S. W. 80 68/100 Leagues.