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appear not, (as when farther srom it:) and consoquently, (though both underthe säme or equal Angles) That near the Horizon is fansied the greater. And.this I judge to be the true Reaibn of that Appearancc.

'<a* txpi/mott VIII. We took a Cylinder of Cast-Braß, AB CD, and cut one end of it%'tbe R $r^b*C D, Perpendicular to the Axis nex, the other End AB, Enclined to itMr.Lowthorp. at an Angle of about 2.7 deg. 30 min. and therefore the Perpendicular toiv. 257. this Enclining Plain p c, and the Axis of the Cylinder ac x, comprehendedrij n j an Angle p c n, of about 6 z deg. zo min. Thde Ends were ground verytrue upon a Glaß-Grinder’s Brasi-Tool, and each of them was compast aboutwith a narrow Feril of thiii Braß Into the upper side of the Cylin-

der, at E, was Soldered the Braß-Pipe E F, and into the under side, at G, theother Brafs-Pipe G H; the former of these Pipes being. about three Incheslöng, and the later 6 Inches. Upon the Piate ddd, were sixt twö otherPlates, L L, Perpendicular to it and Parallel to each other. Each of theletwo Plates had an Arch of a Circle, (whofe Diameter was equal to that ofthe Cylinder) cut out of its upper edge, so that when the Pipe, G H, waslet through a hole near the middle of the Piate, ddd, the Cylinder feli intothe Arches; and being fastned there with Solder,the Axis,a c.v, laid Parallel tothe Piate ddd, and about an Inch .and half abov.e it. The PerpendicularEnd of the Cylinder, DC, was clofcd with an Object Glaß of a 7-5 'FootTeleseope 00, and the Enclining End AB, with a well polisti’d Hat Glaß,ff ; which was carefully chofcn to tranlmit the Object Distinct enough, not-withstanding its Obliqüity to the. Visual Rays. The Feriis were silled withCernent'round about the edges of the GlafleSi, which laid flat and everywhere toucht the soiooth ends of. the Cylinder, that they might firmly sup-port the Weight and Preffure of the Excluded Air.

' S- ri 4 - Instead of a Cistern, (as in the 'lorricellian Experiment) we made use ofthe inverred Siphon of Braß MNO, Solder’d to the Plate ggg. One ofthe Sides M N, stood Perpendicular to the Plate gg g, and the other sidejN O, Enclined to it, and was supported near the upper end O, with -a littlepiece of Brass k.k~

; 'g. 115. We then placed the Cylinder upon a Tabje, which was well fastned -to afirm Floor: The Pipe GH, was let through a Hole in the top of the'Fable, and the Plate ddd, was nailed down to it: The Tube of the Te-leskope m, with the Eye Glaß in it, was applied to the.Object Glaß, and a.Hair fixt at x, the common Focus of both Gkfles, in the Axis ofthe Cylinder continued to it. Upon the Floor ( under the Cylinder) waNailed the Plate ggg, with rhe Inverted Syphon upon it, and joyned. ■ 1 V 1 to.H, by the Insertion of the Glaß Tube T. The Joints were very carefullyclosed with Cement, and. then covered over, with pieces of a Bladder wrapthard with strong Thread.. There was also a . Bladder tied below eachjoint at m, and when it was filted with Water it was tied above it at n \ sothat no Air could come to the Cement, to insinuate it seif through its Porea©r Fiffures, if any happened to be lest undosed. ,,