I saw a flie within a beade
Of amber cleanly buried.

"The Amber Bead" (published c. 1648). Compare: "Whence we see spiders, flies, or ants entombed and preserved forever in amber, a more than royal tomb", Francis Bacon, Historia Vitæ et Mortis; Sylva Sylvarum, Cent. i. Exper. 100. - Hesperides (1648)