A Deception by the Microfcope. 57 
but little larger than that of the real Bodies 
they were drawn from. 
It is very well worth remarking,, that 
amonglt the many pyramidal Figures pre- 
fenting themfelves in a Drop of the Solu¬ 
tion of thefe Salts, every one feems to Hand 
eredt upon its hollow Bate, and appears, 
when under Infpedfion by the Micro¬ 
fcope, exadtly in the fame Manner as repre- 
fented in the Plate: but this is a Deception ; 
for in Double Microfcopes, compounded of 
three convex Glades after the ufual Man¬ 
ner, all the Parts of an Objedt are feen in¬ 
verted ; that is, the Top appears at Bottom, 
the left Side on the right, &c. The Lights 
and Shades being alfo inverted, the linking 
Places appear to rife, and the riling Places 
to link in : fo that iu Truth the hollow 
Bafe of the Pyramid is really uppermoft 
and next the Eye, tho’ it feems to be quite 
otherwife. And in Confirmation of this, 
I was allured by Mr. Lowndes , that in the 
making his Salt, nothing is more common 
than to fee the Pyramids forming upon the 
Surface of the Brine, and always with their 
truncated Ends downwards 
We 
* We are told in the Memoirs of the Royal Academy of 
Sciences for the Year 1700, that Monfieur Homberg Ihewed 
a little Pyramid of Salt, formed in a Cryftallization. It 
was but low in Proportion to its Bafe, hollow within, and 
its Bafe was uppermoi! during the Time of its Formation ; 
which Monfieur Homberg thus accounts for. There was 
formed, fays he, at firft, a little Cube of Salt (the Figure 
Salt naturally affe&s) on the Surface of the faked Water. 
This 
