336 K.rpermcnti on the Hand Grunadc, 



finding they cannot fill the whole space, by close union, 

 on account of their paucity, jnake the best junction they 

 can, by taking a lateral course, and a vacuum is the result 

 of unavoidable necessity. 



And such a vacuum as cannot be produced by any other 

 means that we know of; — a vacuum only assailable by that 

 subtle agent that knows no impediment, 



Put waiks alike through solid gates of brass, 

 Or bars of steei, or doors of molten glass; 

 'ihij prhiut in nwlile iiU forms pervades; 

 Our ev'ry act depends upon its aid. 



It is true, the same event happens to other bodies, upon 

 being brought ii.toa state of fusion and suddenlv quenched, 

 as to glass. Tiius, if a bar of steel be overheated in our 

 attempts to harden it, we see upon breaking it that the in- 

 terior parts have changed their position, and formed them- 

 selves into a kind of irrcjuiar crystals, for the same reasons : 

 yet. as no substance but glass is so generally impermeable 

 to all agents, except fire, the result is not so satisfactory 

 as when this material is used ; because, on account of its 

 diaphanous nature, or transparency, 'the appearances are 

 more ocular, consequently less doubtful. For here, with- 

 out analogy or hypothetical inference, our senses are called 

 to witness the most complete vacuum in nature; and, as 

 far as relates to heterogeneous efliuvia, quite perfect. 



A vacuum not of the Boylean kind, where that air 

 which is driven out is ejected by means of that which re- 

 mains behind; but of the Torricellian kind, yet infinitely 

 more perfect : the very formation of which precludes the 

 possibility of the most subtle agent in nature (except fire) 

 nisinuating one particle of ics substance therein. And, 

 were it possible that we could make this vacuum subser- 

 vient to our experiments on the mechanical pressure of the 

 air, (whether incumbent or lateral,) I am persuaded, from 

 what I ha\'c herein discovered, that we should have a greater 

 result than (the maximum allowed) 14 or 15 lbs. per inch 

 for its energy. The excess of which energy would be iji a 

 direct ratio to the perfection of this vacuum, in coraj)arison 

 with that of the barometer: and those of the a'r-puinp 

 cannot stand one moment in compeiition, for the reason 

 assigned above. 



And yet so well grounded were the anticnt philosophers 

 '* in all space being occupied by some agent or other," that 

 they have, as it were, anticipated us in our most, modem 

 discovery ; i'or it was one of the dogmata of the Peripate- 

 tic or Aristotelian schools, '■' that JNature abhorred a va- 

 cuum." 



