Page 70
In this Table is the Degrees of every quarter Point, ½, and whole Point in the Quadrant; as the first quarter is 2 gr. 49 m. so the half Rhomb is 5 gr. 37 m. the third is 8 gr. 26 m. and the first Point from the Meridian is 11 gr. 15 m. and so you may plainly see the rest.
| Rhombs. | Inclinati∣on to the Meridian. | Number of Leagues. |
| Gr. Min. | Leag par. | |
| 2 49 | 20 2 | |
| 5 37 | 20 10 | |
| 8 26 | 22 22 | |
| 1 | 11 15 | 20 39 |
| 14 4 | 20 62 | |
| 16 52 | 20 90 | |
| 19 41 | 21 24 | |
| 2 | 22 30 | 21 65 |
| 25 19 | 22 12 | |
| 28 7 | 22 68 | |
| 30 56 | 23 32 | |
| 3 | 33 45 | 24 05 |
| 36 34 | 24 90 | |
| 39 22 | 25 87 | |
| 42 11 | 26 99 | |
| 4 | 45 00 | 28 08 |
| 47 49 | 29 78 | |
| 50 37 | 31 52 | |
| 53 26 | 33 57 | |
| 5 | 56 15 | 36 00 |
| 52 4 | 38 90 | |
| 61 5 | 42 43 | |
| 64 41 | 36 76 | |
| 6 | 67 30 | 52 26 |
| 70 19 | 59 37 | |
| 73 7 | 68 90 | |
| 75 56 | 82 31 | |
| 7 | 78 45 | 102 52 |
| 81 34 | 136 30 | |
| 84 22 | 205 14 | |
| 87 11 | 407 60 | |
| 8 | 90 00 | ad infinit. |
As the Sine-Complement of the Rhomb from the Meri∣dian, is to 20 Leagues or 60 Miles, the Measure of 1 Degree at the Meridian:
So is the Radius or Sine of 90, to the Leagues or Miles answering to one Degree upon the Rhomb.
Suppose by the Quadrant it were required to answer this Question,
Sailing N. N. E. from 40 Degrees of North-Latitude, How many Leagues shall the Ship run before it can come to 41? By reason this is the second Rhomb from the Meridian, and the Inclination thereof is 22 deg. 30 m.
Therefore set the side of the Index EL to the second Point from the Meridian N. N. E. 22 d. 30 m. and reckon from C 20 Leagues towards D, and with your Eye or a Pin fol∣low the Parallel-Line to the Index, and you will find it cut 21 Leagues 65 parts (or better than ½ more) the number of Leagues you must Sail before you can reach 1 Degree.
You may do the same by the Travis-Scale thus. Extend the Compasses from 2 Points nearest the end of the Scale, and greatest Number of the Line of Numbers that is N. N. E. 2, and E. N. E. 6 Points, unto 20 Leagues on the Line of Numbers; remove the Compasses to 100 in the Line of Num∣bers, and the other Point of the Compass will reach to 21 Leagues 6/10 ½ or 65 parts, as before in the Line of Numbers.
This may be found also by a Line of Chords and Equal Parts, if you draw a Right Line, and take with your Com∣passes 20 parts, and lay it from one end on the Line; then take 60 deg. and sweep an Arch, and take 2 Points with your Compasses, and lay from the Meridian on that Arch from N. N. E. and draw the Secant or Rhomb-Line, at 20 Leagues draw a Perpendicular or Line at Right Angles there to the former, and measure the distance from the Center, to the Intersection of the Line drawn from 20, with the Rhomb-Line on the Scale of Leagues or Equal Parts, and you will find it the same as before. And so the Qua∣drant shews you all at one sight, if you understand without more words. By the Artificial Sine and Number, Extend your Compasses from the Sine of the Rhomb 67 deg. 30 to 20 in the Line of Numbers, the same Extent will reach from 8 Points, or 90 deg. or 100 in the Line of Numbers, to 21 Leagues 65 parts, as before.— This consider in general; I shall shew you more particularly in 12 Proofs (how of these four, any two being given, the other two may be found, both by Mercator's Chart, and all other ways, as is usual) when I come to treat more particularly of Na∣vigation.