( <*07 ) 
I fhould go on with my Account of this Bode, if it 
could be of any Ufe either to vindicate Sir Ifaac 
Newton , or to convince the Author and his Adherents, 
if he has any. But Sir Ifaac\ Opticks need neither 
Defence nor Explanation. And when the Author is in 
the Humour to be convinced, ten Months well em- 
ployed in reading Sir Ifaac ’s Book, will make him 
amends for his ten Tears prejudiced Examination. 
I beg Leave now to give the particular Defcription of 
a few Experiments I made upon this Occafion, fome 
of which are exactly as Sir Ifaac Newton made them: 
Some are his, but made fomething differently, and 
fome altogether my own. 
Experiment!. F i g. I. 
■4 ' ’ i ’ ' ' 
I prepared a Box of about three Foot high, and one 
Foot wide within (whofe Shape was a truncated Pyra- 
mid) in the following Manner. I painted the Infide of 
it black, and in the back Part, one Foot above the Bafe, 
made a fquare Hole of three Inches in Width (whofe 
Se&ion is rr ) to receive a Piece R Drafting clofe with 
a Rabbet or Shoulder, whofe Surface coming through 
the Hole was wholly covered with the painted Paper, 
on which the Experiment was to be made. Over againft 
r r , in the fore Part of the Box, was a Door to open 
with a Tube in it, four Inches wide and five Jnches 
long, whofe Section is e,fg, h 9 that two Candles feton 
the Places i, k , to enlighten the Paper a^r,r, might 
throw no direct Light out of the Box, whofe Sedion is 
reprefented at abed. Then having made the Room 
perfectly dark, I fixed the Box -upon a Table, that it 
might remain in one Place $ at the Diflance of 
1 eight 
