Mathematical instruments  Book III, Chapter 9, Section 5a
 
5. From the Study of Books we shall proceed next to those Noble Sciences which are gained by their Instructions, which though but a Dead Letter, yet gives Life to all manner of Arts. Now the Instruments which we shall treat upon, are principally such as do measure forth to us both Place and Time; and such as these are used and made for Astronomy, Astrology, Geometry, Navigation, the Art of Dialing, and Clock-work.


Quadrant
 XLVI. He beareth a Quadrant; the Line and Plummet pendant. This is of some called the Compass Quadrant, or Geometrical Quadrant, because the same hath its circumference quarter round, and divided into 90 parts or degrees, being the fourth part of a circle; by the help of this Instrument the height, depth and distance of places are taken and certainly known, and that by the Plumb-line, or shadow of the Sun.


Quadrangle
 XLVII. He beareth a Quadrangle, or a Geometrical square, or Quadrant. The Lines, or Degrees, & Plummet. In this Instrument there are three principal Lines, all the rest are called the scales or degrees.




Jacobs Staff
 XLVIII. He beareth a Jacobs Staff or a Cross Staff; and a semi-Quadrant, of some called a demi-Quadrant, or an Half Quadrant. The Jacobs Staff, of some Writers called the Profitable Rod or Staff. It is a Princely Instrument being set forth in its Perfection; it is a Rod four square, being 3, 4, or 5 foot long, divided into inches all its length; having another cross peece on it, about a foot or two long, having a square hole in the middle, to move too and fro on the long Rod or Staff, and made to tarry on any division, as occasion requireth. By the help of this Instrument, heights, lengths, and breadths of places are taken, see chap.8. numb.169.


Semiquadrant
 In the Base, is another sort of semi-Quadrant, or Octodrant, which I have seen drawn in Mathematical and Geometrical Tables of Instruments; it contains the fourth part of a semi-circle, but of its use I have not yet read.


Circular weather glass
 XLIX. He beareth a Circular Weather Glass. This is a Glass of two pieces, the Shank, which is divided, is put into a Neck in the midle of a Circular Glass, which being three parts filled with a Water made by Art (as Mr. Bate describeth pag.35.) and rarified in the head of the Glass, both being well Luted together, and hung up by a String, then the Water will in Cold Weather ascend the Glass or Shank divided, to 8. 9. or 10 degrees, and with heat it will descend the Shank and mount into the horns of the round Glass.


Perpendicular weather glass
 L. He beareth a Perpendicular Weather Glass set in a Frame. This is a like Glass with a long shank, and a round head, which shank is put through the hole of the Frame, on the top, and so is fixed and Luted into another, at the bottom or foot of the Frame, which is broader below than above; the compound Water (as aforesaid) being rarified in the head of the Glass, will ascend and descend, according to the temperature of the Season. There are double and trebble Glasses, made and set in one Frame, and according to the composition of the Water and rarifying the Air, some Waters will ascend in Cold, and others will ascend in Heat.


Sun dial
 He beareth a Sun dial with its Gnomon, or Cock. There are several sorts of Sun Dials, some for Pillars or Posts, others for Walls, as the following example.


Sun dial
 LII. He beareth a Sun Diall for a Wall, [with] the Cock or Stile, or Gnomon.

Untranscribed item(s) Sun dial parts and terms (Of the sorts of Sun Dials, and the Terms used about them. [Cites ] Jo. Moxons Tutor to Astronomy and Geography, Lib.5. Art of Dialling)

Minute paces of a Clock
 LIII. He beareth the Minute paces of a Clock set on a Stand.


Meridian Spherical Dial
 LIV. He beareth a Meridian Spherical Dial, of some termed a Planisphearal Sun Dial. The use of this Geometrical Instrument, besides the telling of the hour of the day by the height of the Sun, is farther described by Mr Moxon in his Tutor to Astronomy, Lib.5. to whose Works you are referred.


Equinoctial Dial
  This is another sort of pendant Dials, which are hung by the hand, and turned towards the Sun, that by his Beams, darting through small Pin-holes made for that purpose, the hour of the Day or Night may be found. These are commonly called Equinoctial or Universal Dials, and are most used by Sea-Men and Travellers that oft shift Latitudes. [The two drawings (not included on the plate) show an equinoctial dial, folded and open.]


Clock
 LV. He beareth a Clock, or an House Clock; the two side Lids or Windows open, [with] the Finger Board or Figure plate. The Clock consists of two parts, viz. the Watch part, which is always in motion, and the striking part, which only goes about when it striketh the Hours, of which several parts take the denominations of them from the Watch, as in numb.57.


Hour glass
 LVI. He beareth an Hour Glass.


Watch
  LVII. He beareth a Watch, (or an Hour Watch,) with its Cover open, and the Key in Base Chained to the Watch.

Related text(s)   Watch parts

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