I just added the below image and caption to the Trombone History Timeline (17th century, 2nd half).

c. 1675—Bern, Switzerland: The title page of Johann Ulrich Sultzberger’s book of transposed Psalm settings, Dr. Ambrosii Lobwassers Psalmen Davids, features an image with a trombone and cornetto suspended together (see upper-middle of below image; public domain). Special thanks to Bruce Dickey.