uch Oyls as are made by expression, which are easily
discovered by rubbing them on white paper, which being held and dryed
at the fire, the Chymical part soon flyes away, and leaves the paper
transparent, looking no otherwise then oyled paper; but pure Chymical
Oyls totally fly away, leaving the paper white as 'twas before, and
not transparent, and in this way Oyl of sweet Almonds and Spike have a
great share. As for Oyls drawn by Retort, they all of them smell so
strong of the fire, that neither smell nor tast can well discover any
fraud in them. Now for the fixed Salts, most of them are made of the
Ashes of Tobacco-stalks, &c. More might be said for the discovery of
the Cheats of other Chymical preparations, which shall be reserved to
another opportunity, and had Physicians just encouragement, they would
spend both their time and moneys on the like discoveries for the
publick Utility.

Fifthly, Add to the former (though perhaps 'tis an error of ignorance
only) that if such Simples are prescribed they know not, they fetch
from the Herb-women what they give them, true or false; for many of
these Women give to very many Plants false names; Now if the
Apothecary be so careful to consult an Herbal, which few have, and
fewer know how to make use of, yet they too frequently mistake the
thing by reason of several names given to the same thing, or of one
name to several things, and many of them consult the common
Dictionaries only, which are most erroneous in the names of natural
things; insomuch that in my first practice (being curious of these
particulars) I have found two or three mistakes in one prescription, a
Catalogue of which mistakes, and names ill given, I had collected, but
the late fire consumed it, though many of them my memory hath
reserved.

Sixthly, Many of the London, and most of the Country-Apothecaries, buy
of the whole-sale men, who affirm of one another, especially of such
who gain great Estates in short time, that they cannot sell their
Medicines honestly made at so low a rate as they do.

Seventhly, I shall need to say little of such distilled waters, as
discover themselves neither to smell, nor tast, but shall only recite
a known Story of an Apothecary, who chid his man for sending away a
Customer that came for Plantan water, telling him there was enough at
the Pump.

Eighthly, As for Ointments, and Plasters, they are sold by some at so
low a price, viz. 3 d. per l. for Ointments, as I have been in