Horologiographia nocturna. Or Lunar horologiographie Set forth and demonstrated (after a twofold manner) in the horizontall plane onely. Vpon which (and all other by the same reason) may in a manner, as plainely and speedily bee discerned the times of the night by the gnomonicall shadow, caused by the moone, as the times of the day upon any by the sun: serving as well in the day time for the sunne. By Iohn Wyberd. Together with an addition of certaine new and briefe rules for the exact and most speedy mensuration of circles and spheres, and also cylinders, both in solid and liquid measure, by certaine plaine scales onely, not heretofore published, but now set forth for the benefit of all those that have occasion to make use of such things.

The use of this Gauging Ruler is thus.

First finde the equated diameter, as before. Then multiply the square of the equated diameter by the length of the vessell; the product is the content in wine Gallons.

Example.

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Another Example.

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〈 math 〉〈 math 〉 Equated diame∣ter: Or I might here take 26, be∣cause the fraction approacheth nigh unto an unitie: for in this kinde of mixt numbers, when the last figure of the fraction towards the left hand exceedeth the number of 5. there (to a∣voyd the fraction) you may adde an unitie to the whole part thereof, and so make it an absolute number, and when it wants of 5. (as in the last fraction) you may (if you please) reject the fracti∣on (which will breed no sensible errour in the worke) and retaine the whole number onely, or you may cut off all the figures (if there be many) saving the last two or three towards the left hand, and so make it onely a centesimall or millesimall fraction: So the fraction of the last number afore∣going, may be onely. 24, which here signifieth very neare ¼ of a Gallon.

The question in this last example, is as difficult as most that you shall meete with of this kind, and therefore if this be rightly understood, all other questions of the same nature may be easily under∣stood.

Here I might have shewed the use of some o∣ther scales for this purpose, and likewise the man∣ner of taking the diameters of vessels at the head and bongne by this Ruler, but that this is a thing

not unknowne to such as are exercised in gauging of Vessels, the same being fully shewed in bookes of gauging already published and therefore mine intention was not, here to set downe the whole Art of gauging, but briefely to shew the making and use of this gauging Ruler, which was never published before, although I could have set forth the same long before this time; and there∣fore if any shall thinke good to make tryall of this or any of the rest which I have here delivered, let them speake of them according to what they shall finde in them, and not otherwise.