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Mathematical instruments (continued) Book III, Chapter 9, Section 5b Chapter 9, Item 59a Compass points The names of all the Points of the Compass. [Not further transcribed] Where note that the two Poles North and South, have the greatest denominations of all the other points, being each eleven, viz. the full North and 10 Northerly points; and the full South and 10 Southerly points; whereas the East and West have their full points, and each four Easterly and Westerly points. Back to Text & Pictures Chapter 9, Item 62a Magnifying glass It is called a Magnifying Glass, when looked through to behold another thing behind it; in which respect these kind of Glasses (being thick in the middle and thin in the sides) will make any thing on the farther side of it to appear twice or thrice, or more times, bigger than they are; of this Nature are Spectacles which are made for Old Ages. Back to Text & Pictures Chapter 9, Item 62b Burning glass It is termed a Burning Glass, being held at a certain distance from any combustible matter, and in a direct Line between the Sun and the said matter, it will in a short time Fire the same. Back to Text & Pictures Chapter 9, Item 62c Seeing glasses types Several sorts of Seeing Glasses. Looking Glasses to see ones Face therein. Spectacle Glasses, Eyes for Old People. Perspective Glasses, to see things afar off. Optick Glasses, which represents things several ways. Magnifying Glasses, which makes things great. Diminishing Glasses, that makes things seem small. Prismes Glasses, which represent things of diverse colours, as red, green, yellow, like a Rain-Bow. Burning Glasses, that Fires any thing by the Sun. Convex Glasses, which shew things upside down. Back to Text & Pictures
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