Gall, _Copper_ and _Iron_ of most _loathsome_ tasts. And indeed the
business of this sense being to discover the presence of dissolved Bodies
in Liquors put on the Tongue, or in general to discover that a fluid body
has some solid body dissolv'd in it, and what they are; whatever
contrivance makes this discovery improves this sense. In this kind the
mixtures of Chymical Liquors afford many Instances; as the sweet Vinegar
that is impregnated with Lead may be discovered to be so by the affusion of
a little of an _Alcalizate solution_: The bitter liquor of _Aqua fortis_
and _Silver_ may be discover'd to be charg'd with that Metal, by laying in
it some plates of Copper: 'Tis not improbable also, but there may be
multitudes of other wayes of discovering the parts dissolv'd, or dissoluble
in liquors; and what is this discovery but a kind of _secundary tasting_.

'Tis not improbable also, but that the sense of _feeling_ may be highly
improv'd, for that being a sense that judges of the more _gross_ and
_robust motions_ of the _Particles_ of _Bodies_, seems capable of being
improv'd and assisted very many wayes. Thus for the distinguishing of
_Heat_ and _Cold_, the _Weather-glass_ and _Thermometer_, which I have
describ'd in this following Treatise, do exceedingly perfect it; by each of
which the least variations of heat or cold, which the most Acute sense is
not able to distinguish, are manifested. This is oftentimes further
promoted also by the help of _Burning-glasses_, and the like, which collect
and unite the radiating heat. Thus the _roughness_ and _smoothness_ of a
Body is made much more sensible by the help of a _Microscope_, then by the
most _tender_ and _delicate Hand_. Perhaps, a Physitian might, by several
other _tangible_ proprieties, discover the constitution of a Body as well
as by the _Pulse_. I do but instance in these, to shew what possibility
there may be of many others, and what probability and hopes there were of
finding them, if this method were followed; for the Offices of the five
Senses being to detect either the _subtil_ and _curious Motions_ propagated