[272] 
IX. ExtraB of a Letter from Dr. Jofephns 
Laurentius Bruni, of Turin, F. R. S. to Mr. 
Henry Baker,. F.R.S. concerning the Bologna 
Bottles. 
Bated at Turin, Nov. ~-f 1744. 
Dear Friend , 
Read Jan. 3 T -'~| HE Seed of the Gramen tremulum *, 
1744 5 ' A which you favoured me with, has 
amazed all here who have feen it. The curious 
People iu this Country talk much ora Parenomenon, 
which is called of the Bologna Bottle, becaufe ir was 
firft difcover’d at Bologna. If yoij jet thefe Lotties fail 
perpendicularly from fome Height' upon a Brick- 
Floor, they will not be broken j but if you drop into 
them fome little hard Bodies, they will burft in Pieces. 
1 will give you an Account of what I try’d myfelf 
about them. 
I took one of thefe glafs Bottles, whofe Form re- 
fembles a Florence Flask, and Whofe Capacity is about 
three Quarters of a Pint, and let it fall down from 
the Height of five Feet and half upon a Floor of 
Brick, and it was not broken : I then let fall down 
into it, from the Mouth to the Bottom internally, a 
Piece of Flint-Stone, weighing 1 1 Grains ; and imme- 
diately the Bottle burft into many Pieces. 
I took one of thofe Pieces, weighing a Dram, and 
let it fall in the fame manner into another Bottle, 
which I moved circularly for a Minute ; and then 
putting 
* See the/e Tranfadtions, N°, 457. 
