Brown Gnat (from Favorite Flies and Their Histories - 1892 - by Mary Orvis Marbury)

as illustrated by Charles Orvis

Hook: gnat size (here #14)
Tag: gold tinsel
Body: brown chenille
Wings: brown dry fly hackle tips

Head cement recipe:
Goop
Xylene (epoxy thinnner)

Instructions:
Fill a quart jar half full with Xylene
Squeeze a tube of Goop into the Xylene
Shake until the Goop is dissolved; add Xylene to desired consistency

Apply with a pin or needle dipped in the liquid

https://youtu.be/AJbvJUixaCs