This poem is from a book entitled Adagiorum Maxime Vulgarium Thesaurus, first published in 1730.
In Medio Securus
In medio securus eris; dum prendere summa
Quaeris, in adversum culmine saepe cadis.
The vocabulary is keyed to the DCC Latin Vocabulary list. There are only two words in this poem that are not on the DCC list:
culmen (culminis, n.): peak, top, height
prendō, prendere: catch, grab, seize
adversus -a -um: facing, opposed; unfavorable; adversus (-um): (adv. and prep.) facing, opposite, against, opposed (to)
cadō cadere cecidī cāsum: fall, be killed
dum: while (+ indic.); until (+ subj.); provided that (+ subj.)
in: in, on (+ abl.); into, onto (+ acc)
medius -a -um: middle, central
quaerō -rere -sīvī-situm: seek, inquire
sēcūrus -ā -um: free from care, tranquil; careless
sum, esse, fuī: be, exist
summus -a -um: highest, farthest, last