[ 579 ] 
Mr. Robins not having been able to obtain any 
certain Account to what Diftancc any of thefe 
Rockets were actually feen, and confidcring the great 
Ufe that might be made of Rockets in determining 
the Portion of diftant Places, and in giving Signals 
for naval and military Purpofes, he refolved to or- 
der fome Rockets to be fired at an appointed Time, 
and to defire fome of his Friends to Iook out for 
them at fcveral very diftant Places. 
The Places fix’d upon for this Purpofe, were, 
Godmarjharn in Kent , about 70 Miles diftant from 
London ; Beacon Hill on Tiptery- Heath in Effcx, 
at about 40 Miles; and Barkway , on the Borders 
of Hertfordjhire , about 38 Miles from Londoji. 
Mr. Robins accordingly order’d fome Ro:kccs to 
be made by a Perfon many Years employ’d in the 
Royal Laboratory at Woolwich ; to which fome 
Gentlemen, who had been inform’d of M r. Robins’s 
Intentions, added fome others of their own making. 
The 27th of September, 1749- at 8 in the Evening, 
was the Time appointed for the firing of them ; but, 
thro’ the Negligence of the Engineer, they were 
not let off till above half an Hour after the Time 
agreed upon. There were in all- a dozen Rockets 
fired from London Field at Hackney j and the 
Heights were meafur’d by Mr. Canton , Mr. Robins 
being prefent, at the Diftance of about 1 200 Yards 
from the Poft from whence the Rockets were fir'd. 
The greateft Part of them did not rife to above 
400 Yards; one to about 500, and one to 600 
Yards nearly. 
By a Letter I receiv’d the next Day from the 
Rev. Dr. Mafon y of Trinity College , Cambridge , 
E e c e who 
