Definition of "unmingled"

In order to the diſcovery of ſome hints of the account, upon which the above mentioned mixtures were more intenſely frigefactive than ſnow alone, we ſealed up a ſingle vial of ſnow unmingled with any other ingredient, and found it to thaw much more ſlowly than any of thoſe parcels of ſnow, which we had mixt with ſalts or ſpirits.

1663, Robert Boyle, “Title I. Experiments Touching Bodies Capable of Freezing Others.”, in New Experiments and Observations Touching Cold, or, An Experimental History of Cold, Begun. […], London: […] Richard Davis, […], published 1683, paragraph 13, page 49