( Si ) 
Thus in Seftion XVII, he lays upon the Ground a 
Board two Foot and a half long, eleven Inches broad, 
and two Inches and a half thick, with a Quarter of 
a Sheet of Writing-Paper upon it, having about an 
Inch hanging over one Edge of if. 
To fecure the Paper from being removed out of its 
Place by the Wind, he fattens it with an Awl ftuck 
perpendicularly, having a round wooden Handle, and 
lays a Knife with a cylinaric wooden Handle, as an 
additional Weight. Upon liis Return to fee what 
EffeQ: the Dew had upon them, he found that the; 
fmall Part of the Paper which was extended over the 
Edge, was moiftened with Dew, while the reft of the 
paper, as alfo the upper Surface of the Board, were 
dry, but the upper Parts of the Handles of the Awl 
and Knife all wet. 
An Experiment fomethihg a-kin to this was made 
with a Glafs Tube laid horizontally upon a JBrafs 
Plate fourteen Inches fquare, having about two Inches 
and a half reaching beyond the Side of the Plate. 
The Tube was kept from rolling by two Paralle- 
lepipeds of Lead. The'Evenf was^ the whole Sur- 
face of the Tube was bedewed, while the upper Sur- 
face of the Plate remained dry. 
In Section XXI, XXII, we have a Set of Experi- 
ments made with concave Veffels, having their Mouths 
upwards, and placed at different Elevations above the 
Earth. In thefe Cafes alfo he found no Dew at the 
Bottom of their Cavities, nor on the Sides, except 
within about an Inch near the Brim. 
Since Hoar-Froft is only common Dew congealed, 
he applied himfelf to make fome of the fame Kind 
of Experiments upon that, with Brafs Plates laid upon 
the 
