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ration, as it moft frequently docs, it forms the little 
pyramidal Mafs, which is known by the Name of a 
Glafs-Drop ; the EfFe&s whereof I will firft relate, 
and then endeavour to account for them. 
Experiment i. This Drop is of fuch Hardnefs and 
Refiftance, that it bears fmart Blows of a Hammer, 
without breaking. 
Exper. 2. Nevcrthclefs, if you grind the Surface 
of this Drop which refitted the Hammer, or if you. 
only break the Tip of the fmall End or Tail, the 
"Whole fhatters into Powder. 
Exper. 3. This Shattering of the Drops is attended 
with a loud Report; and the Duft or Powder to 
which it is reduced, fhoots out, and fcatters all 
around. 
Exper. 4. If the Drop be ground with Powder 
of Emery, imbibed with Oil, it often elcapes 
breaking. 
Exper. y. If this Experiment be made in the 
Air-Pump, the Drop burfts with greater Impetuofity, 
fo as fometimes to break the Receiver and its Duft 
js finer than when done in the open Air ; and if it 
be made in the dark, the Drop in burfting produces 
a little Light. 
Exper. 6. If this Drop be annealed in the Fire, 
it lofes all thefe Singularities ; and being reduced 
to the State of common Glafs, it eafily breaks un- 
der 
