Century . L 
den with rime : Alfothe Induration of Head-Amber, which ar I- 
firJt is a (oh Subfiance ; as appeareth by the Flies, and Spiders, ! 
.which are found in it j And many more: But We yvili fpeakcol J 
them diitin&ly. 
For lndurationsby Cold, there be few Trials of it • For we haue no ftrong 
orintenfe Cold hereon the Surface of the Earth, foneere theBeames of 
theSunne,andtheHeauens.ThelikelieftTriallisby 5 ’»<ur l and Ice^ For 1 
as Snow and Ice, especially being holpen, and their Cold adiuated by NT 
tr e,or Salt, will tumc.wafer into Ice, andthacina fewhoures • So it may 
bee, i t will tume wood, or Stiffe Clay, into Stone, in longer time. Put there¬ 
fore, intoa Conferuing Pit of Snow , and Ice, (adding fome quantity of Salt, 
and Nitre,) a Peece o iwood^ or a Peece of Tough Clay, and let it lye a Mo- 
I nethjOr more. 
• Another Triall isbv Metalline waters, which haue vertuall Cold in 
them. Put therefore Wood, or Clay, into Smiths Water, or other Metalline 
Water • And try whether it will not harden in fome reafonable time. But I 
vnderltand it, of Metalline waters,that come by Wafhing, or Quenching- 
J And not of Strong waters that come by diflolution • for they are too Coro- 
.| jfiuetoconfblidate. 
| It is already found, that thcreare fome Natural/Spring-waters, that will 
J Inlapidate wood ; So as you fhall fee one peece of wood , whereof the Part 
aboue the Water (hall continue Wood 5 and the Part vnder the water fhall 
be turned intoa kinde of Grauelly stone • It is likely thofe Waters are of 
fame Mt tall;t?e Mixture - 3 But there would bee more particular inquiry 
made of them. Itis certainethat an Egge was found, hailing lien many 
yeares in the bottomeof a Moat, where the Earth had fome what ouer- 
growneitj And this Egge was come to the Hardnelle of a Stone , And 
had the Colours of the white and yolke perfect : And the Shell tinning in 
fmallgraines like Sugar, or Alablafter. 
Another Experience there is of Induration by Cold, which is already j 
found; which is,that MetaUsyhemfduesare hardned by often Heating and 
Quenching in Cold Water: For Cold euer worketh molt potently vpon Heat ; 
precedent. j 
For Induration by Heat, it mud be confidered, that Heat, by the Exha¬ 
ling of thcMoifter Parts, doth either harden the Body ; As in Bricks, j 
Tiles, See. Or if the Heat bee mote fierce, fnaketh the groflfer part it feife* I 
Hun and Melt • As in the making of ordinary Glaffs • And in the Vttrt- > 
feat ion of Earth, (As wee fee in the inner Parts of Furnaces ; ) and in the I 
r/trifeat ion of Bricky And of Met alls. And in the former of rhefe, which 
is the hardning by baking, without Melting, the Heat hath thefjb degfeesi 
Firft, it Indurateth • And then mak£th Fragile *, And lalf ly it doth Incine¬ 
rate and Calcinate. 
i But if you defire to make an Induration with Toughnejjs, and Iefle | 
Fragility ; A middle wav Would be taken; Which is thatwhich Ariflotle j 
' hath Well noted; But would bee throughly verified. It is to decod Bodies 
