XI. An Account of fome Experiments , made 
' by Benjamin Robins Efq\ F. R. S. Mr. 
Samuel Da Cofta, and fever al other Gentle - 
men, in order to difcover the Height to 
3 •which Rockets may be ?nade to afcend , and 
l to what Dijlance their Light may be Jeon \ 
by Mr. John Ellicott F. R. S. 
nr '-jrj i- • f i .• .... , | 
Read Dec.^oON after the Exhibition of the Fire- 
|.3- i/5°- works * in th t Green : Park, Mr. Robins 
communicated to this Society an Account of the 
Height to which feveral of the Rockets there hred 
were obferved to rife. In this Account, after hav- 
ing given a fhort Defcription of the Inhrument with 
which the Heights were meafured, he obferves, that 
the cuhomary Height to which the fmgle or hono- 
rary Rockets, as they are hiled, afeended, was about 
4 6 y Yards? that three of them rofe to about yyo 
Yards j and the greateft Height of any of thofe 
hired in the grand Girandole was about 6 oo Yards. 
He like wife further obferved, that, fuppoiing Roc- 
kets are made to afcend 6oo Yards, or more than a 
Third of a Mile, it follows, that if their Light be 
fufhciently ftrong, and the Air not hazy, they may 
be feen in a level Country at above yo Miles Di- 
ha nee ; and that, from the Nature of the Compo- 
htion, and the ufual imperfed Manner of forming 
them, he j was of Opinion that Rockets were capable 
of being greatly improved, and made to reach much 
greater Dihances. 
Mr. 
* On Occafion of the late Peace, 
