_The thirteenth_ Experiment, _of Changing the Blackness of some Bodies into
other Colours_ (171, 172.) _and of Whitening what would be Minium, and
Copper, with Tin, and of Copper with Arsnick, which with Coppilling again
Vanishes; of covering the Colour of that of_ 1/3 _of Gold with_ 2/3 _of
Silver melted in a Mass together_ (173, 174)

_The fourteenth_ Experiment, _of turning the black Body of Horn into a
White immediately with Scraping, without changing the Substantial form, or
without the Intervention of Salt, Sulphur, or Mercury_ (176.)

_The fifteenth_ Experiment, _contains several Instances against the Opinion
of the_ Chymists _that Sulphur_ Adust _is the cause of Blackness, and the
whole Matter is fully discuss'd and stated_ (from 176 to 184)

Part the Third.

_Concerning Promiscuous Experiments about Colours_.

Experiment the First.

_IN confirmation of a former Conjecture about the Generation of Colours
from diversity of Reflections are set down several Observations made in a
Darkned room_ (186, 187.)

Experiment _the second, That white Linnen seem'd Ting'd with the Red of
Silk plac'd near it in a light Room_ (188,189.)

Experiment _the third, Of the Trajection of Light through Colour'd Papers_
(189, 190.)