Part IV. And Statural Pbilofophy* 557 
correfpond with all thofe experiments 5 and will be too long 
to fuit with this Catalogue. 
I fhall here only fay, I am inclined to believe, That, in 
this Cafe, all the three Bodies above mention d ferve toger 
ther to compofe an Apt Recipient of that which is the 
frue Luminous Body. That, as in the mixture of .Sulphur 
and Water , fulphurious Salts , of affinity with both, are 
ufed as a medium : fo here, the Cretaceous Parts ferve to 
fix the Nitrous 3 and the Nitrous, to hx the Igneous 3 being 
of a middle nature and readily incorporated with them 
both. And being in this union expofed to the Sun Beams, 
or other Light, the Igneous parts ferve,for fome time, to re- 
tain a certain portion of fuch as are Luminous, or to give, 
as I may fay, a degree of Fixation to Thefe alfo : and that 
therefore this Mixture is kindled or made to fmne,by puting 
it into the Light 5 as a flick is made to burn, by puting it into 
the fire. 
Of fliining Flefh, fee a Relation of fome Remarkable 
Circumftances, made by Dr. J. Beat, and publifhed in the 
Phil. Tranf. (a) CON. 125, 
Of luftruments relating to 3\(atural Thihfyhy. 
AN AIRE-PUMP5 or an Engine to exhauft the Air out 
of anv Veffel fitly applied.Contrived and defcnbed (b) ( h ) Expert 
by the Honourable Rob. Boyle ^ Who hath alfo made fiTmcbl 
tnerewith, and publifhed in feveral Tracts, a great variety *H of " the 
of accurate and inftrucTive Experiments. • tRt ° f 
A Great CONDENSING ENGINE of Brafs 3 con- 
trived to ram and crowd a great quantity of Air into a 
little room. Whereto is alfo fitted an Iron Gun or 
Barrel 
A Little CONDENSING ENGINE of Glafs , with a 
Brafs-Neck, Rammer and Valve fitted to it. 
A WEATHER CLOCK. Begun by Sir Chr. Wren, (c) (c) &e M. 
now Prefident of the Royal Society. To which other f 0 J^ Royd 
Motions have fince been added , by Mr. Robert Hooip.312] 
ProfefTor of Geometry in Grefham-Colledge. Who purpofes 
to publifh a Defcription hereof. I fhall therefore only take 
notice, 
