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Seconds.

A piece os a Chambcr-Quarry-Stonc was Virrificd, and put into 7

a Olafs drop, in>----— 3 ^

Steel, whereof Watch-makers make their Springs, was found?

melted, in ■ — 1 ■ 1 ■ . 5°9

A Mincral-Stone, such as isusod in Harquebuffes a rcz-et, was Cal -7

cin’d and Vitrihed, in-—-- - --- S°

A piece of Morter was Vitrified, in*---, - p.

IbLl. p. 97.

n. 49. p. 986.

.AnOther by trjtsamt,

ir. 49 - P- ? 8 <fr

iy S. Settalla.tu 40. f. 7 96.

In Ihort, There is hardly any Body which is not deflroycd by this Fire.If one would Melt by it any great quantity of Metal, that wotild requiremuch time, the Action of Burning not being performed but within the big-ncis of the Focus, iö that ordinarily none but imall pieces are cxposcd to it.One M. de Alibcrt buys it, paying for it 1 yoo Livres.

You encline to believc, That the Glasses of Maginus and Sepulius do ap-proach to that of Lyons But Ican assute you, they come very far ihort of it.You may consuit Maginus his Book, whcre he describes his; and’ thorc areforne Persons here who have seen one of his beti, which had but about 2©Inches Diameter; so that this of Lyons muli perform at leail twice as much.As to Septalius , we expect the Relations of it from Intelligent and ImpartialMen. It cannot well be comparedto thatio i Lyons, but in bigneis; and inthis caso, if it have sive Palms, (as you iay) that would be about 3 '- FootFrencb, and so it were a Foot bigger, which would make it half -as muchgreatep in Sürfaee : But as.to the Effects* seeing it Bums so far off, theycannot be very violent. . And I have heard one iay, that had soen ir, that itdid not set Wood on Fire but aster the time of faying a Miserere. You mayjudge of the difference of the Effects* fince that of Lyons gathers its Beamstogpthet within the ipace of 7 or 8 Lines ; and that of Septalius null soup-ier them in the compais of 3 Inches.

It was diipofed of -to the Kihg of Dennutrk.

2. The fame M .de Vilettc of Lyons hath made anather Burning Concave.It is of 34 Inches Diameter, and Melts all sorts of Metals, and Iron it ielfof the thicknesi of a Silver Crown, in leis than a Minute of time,, and Vi-trifies, Brick in the iame time; and as for Wood*, whether Green or Dry, itsots k on Fire in -a moment. The.King hath soen it, and the Performance?of it, with great Satisfaction ; and his Majesty is likely to make it his, andth?n to bestow k on his, Ryyal Acadcmy of Philosophers, ibr makiug of fai*-ther Experiments with it.

This kind of Concaves Burning the moss forcibly of any Fire weknow of, would be of great uso, if they could be so contrivcd as to have nFocus of .any-considcrable largenefs, to take-in agood quantity of conibusti'ble matter at once.

3. : S. Stttalla at MUm* causoth .ro be made a Burning Glasi of soven Footin Diameter. He pretends to make it Bum. at the diltancc of 50 Palms,which ii about 3 z Foot»

4» The