[ '82 ] 
• I * I • p 
In the Second of thefe Experiments, the brafs 
Chamber, not being fufficiently thruft home before 
the Difcharge, was by the Violence of the Powder 
driven in fo, that it could not be got out again without 
the Help of an iron Screw, and a vaft Force applied 
to iron Wedges. This was doubtlefs the Caufe 
of the great Irregularity obferved in this Cafe. The 
mean Diftance, colle&ed from the other Three Experi- 
ments, is nearly 741 Feet. 
Then Three Difcharges were made with the Cham- 
ber Three-fourths of an Inch deep, with Ball, Powder 
and Elevation, as before. The Ranges were. 
Shot. 
Chains . 
Links. 
• 
I. 
7 * 
6. or 
466 Feet nearly. 
II. 
7. 2. 
463. 
III. 
**> 
S • — - 
463. 
The mean 
Diftance to which 
the Bail was thrown 
in thefe Three Experiments is 464 Feet. 
The Chamber One Inch and. an half deep, was alfo 
tried > but this not fitting the Mortar fo well as the 
other Two, the Ranges were found to be very irre- 
gular, being 
Shot . Chains . Links . 
I. 10. 40. or nearly 68 6 Feet. 
II. 9. 6. 598. 
III. 7. 8. t 467. 
The laft Shot, failing fo much fhort, may be afcri- 
bed to the Damp, it being late in the Evening when 
it was fired. 
That Moifture greatly weakens the Effect of Pow- 
der, is commonly known ; and the Committee found 
by an Experiment, That Powder dried by means of a 
Phial in Balneo , and put warm into the Chamber, 
threw 
