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Mathematical Instruments Book III, Chapter 8, Section 14 Chapter 8, Item 166a Quadrant parts The parts of the Quadrant. The Centre, the Angle where the Label is fixed. The Sides, the streight which makes the Angle. The Limb, the round part on wich the Figures and Lines are made. The two Sights fixed on the moveable Index. The Index, or Label, that which moves on the Centre pin. The Handle, that by which it is held. The Pin of the Index. The Figures and Altitude Lines. Back to Text & Pictures Chapter 8, Item 167a Astrolobe parts The parts of an Astrolabe. The Circle or Ring, about which the Figures are made. The Perpendicular Line, the Down Bar in the Circle. The Level Line, or Horizon Line, the over-cross Bar. The Degrees, the Figures and the Lines about the Limb. The Center, the middle of the Circle. The moveable Label or Rule. The Sights or Vanes, the holes to look through. The Points of the Rule. The Eye, that in which the Ring hangs. The Ring. Back to Text & Pictures Chapter 8, Item 169a Paralaligreme parts Parts of a Paralaligreme. The four Rules, which are marked with figures Holes. The four Pins, that holds them together. The four Nuts, that holds the Pins in their places. The Center Pin, which is an Iron pin made fast in a place that it comes not out, but let the Ruler turn upon it. The Black lead Pencil, which is to draw on a fair Paper which it is moved too, it is fixt at the end of one of the long Rulers. The Point, being an other wooden Pin with a sharp end: The Instrument being thus sited and Fixt, if you lay a Printed draught under the Point and trace the figure over, what you do on the print, the other end with the Black lead will draw the like on a Paper layed under it, which an Artist or any person by sight, with a litle Instructions may be able to draw any thing by a Patern, big or litle as I have aforesaid. Back to Text & Pictures
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