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tcct all thc m/stüte Väriations in the pressure änd weight of Air. Withthis Instrument he made divers Obfervations in the year 165-9, an ^ 1 650,before any others w ete publick, or by him so much as heard of.

x. Dr. J. Beal is so much pleased with the diseovery already made by thehelp of this Instrument, that he thinks it to bc one of the most wonderfulthat ever was in the World. For (Taith hej who could ever expect, thatwe men Ihould find an Art, to weigh all the Air that hangs over our heads,in all the changes of st, and as it were to weigh, and to distinguilh byweight, the Winds and the Clouds ? Or who did believe, that by pal-pable evidence, we Ihould be able to prove, the serenest Air to be the mostheavy, and the thickest Air, and when darkest Clouds hang neerest to us,ready to dissolve, or dropping, then to be Iightest ?

1. My Whed Barometer I could never fill so exactly with Merdury, asto exclude all Air; and therefore I trust möre to a Mercurial Cane, and takeall my Notes from it, this Cane is but 35 Inches long, of a very slendcrCavity, and thick Olafs.

x. In all my Obfervations from May 28. 1664. to this present (De-cember 9. 1665 .) the Quick Silver never ascended but very little aboveInches.

3. It ascended very feldom so high (viz. to 30 \ Incheschießy in De-cember 13. 1664. the weather being fickle fair, Evening.

4. I find by my Calender of Jtme zz. 16-54. at 5 in the Morning, ina time of long fetled fair weather, that the Mercury had ascended abouthalf an Inch higher than 30: but I fearsome mistake, because I then tookno impreflion of wonder at it; yet for 3 or 4 days, at that time it conti-nued high, in well letled fair and warm weather; most part above 3 oInches. So that I may note the Mercury to rise as high in the hottest Sum-mer, as in the coldest Winter-weather.

5. Yet surely I have noted it ascend a little higher for the coldness of theWeather; and very frequently, both in Winter and Summer, to be higherin the cold Mörnings and Evenings, than in the warmer mid-day.

6. Generally in letled and fair Weather both of Winter and Summer,the Mercury is higher than a little before, or after, or in rainy weather.

7. Again, generally it descended lower after Rain, than it was beforeRain.

8. Generally also it falls in great winds; and somewhat it scemed tosink, when I opened a wide door to it, to let in stormy winds; yet Ihaye found it to continue very high in a long stormy wind of thrce or fourdays.

9. Again, generally it is higher in an East and North Wind (caterisparibus) than in a South and West Wind.

10. I tryed' several times, by strong Fumes, and thick Smoaks, to alter theAir in my Closet; but I cannot affirm, that the Mercury yielded any more,than might be expected from some increase of heat- Such as have exadfcWheel Barometers, may try whetheV Odo'fs or Fumes do alle viate theAir.

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By Dr.]. Beal.ib. p. 1J4.

ib.p. t ss-

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