Z55

O K

THE

SEVENTEENTH B O

O F

Natu ral Magick:

O

Wherein are propounded Burning-glalles, and the

wonderful sights to be ieen by them.

ThbPro'emb.

N O to I am come to Mathematical Sciences, and. this place requires that I shew some ex-periments concerning (fatoptrickf glasses. For these jhtne amongst Geometricalmslru-ments , for Ingenuity , tn'ouder, and Frcfit: For what could be invented more ingeniously,then thai certain experiments jhculdfolkw the in*igiK»ry conceits of the mind , and the truthof <^filathcniattccl‘Dimi xsfraiio>.s should be made good by OouUr experiments ? what couldseem more wonder ul, then that by reciprocalsirckys of rtfixton, Im.ge should appear out-wardly , hanging in the Air, and jet neither the visible OljcSt nor the Glass seen I that theymay set m not to be the refer e fission of the Glasses, but Spirits of vain 1‘hart asms t to feeburning CUfos , not to burnalcne where the beams unite , but at a great distance to castset th terrible fires, andfiames , that are nsefi profitable in warlike expeditions , as in many o-thtt things. We read that Archimedes a- Syracuse with burning Glasses defeated the forcesoj the Ri-mans: and that King Ptolctney built a tower in Pharos , where he ft a Glassythat he could for fix hundred miles , fe by it the''enemies Shps , that invaded his Country,ar.d plundered it. 1shall adde also those Speflacles , whereby ptor blinde people can at greatdistance, perfeBly fe aUthtrgs, And though venerable Antiquity seem to have inventedmany and great things , jet I shall set down greater, more N? ble , and mere Famou: things,and that will not a little help to the Opt ck,Scierce, that more sub/me wits may increase itinfinitely. Lastly, IskaHskew how to make (frysal and Metal Glasses, and how to polishthem.

Chap. I.

‘Divers representations made by plain Glasses.

f

i Shall begin with plain Glasses, fer they are more simple, andthe (peculations thereof, are not so laborious, though the ap-paritions of them be almost common, yet they will be usefulfor what follows : and we shall add seme secret apparitionsunto them. The variety of the Images that appear, proceedeither from the matter or formes the Glass. Crystal mult beclear, transparent, and exactly made plain on both sides: ardif one or both of these be wanting , they will represent diversand deformed apparitions to outfight, 1 shall therefore beginfrom the matter, and shew

How apparitions may seem to him that looks upon them , to be pale. yellow, or of divers eolettrs.When the Glass h melted with beat in the furnace , wish any litrle colour v will b etainted ; if you cast in yellow, the face cf him that locks irio it, will ieem r o havethe yellow Jaundies - it b'ack, he will appear wan and deformed; if you add much cfu, like to a blackmoore; if red, like a drunkard or furious fellow; and so will it re*

Bb 4 present