The following poems are just a few of the many that appear as uncollected poems in Collected Poems, Prose, & Plays. I have chosen the poems below because each one contains noteworthy scientific or technical content. The earliest poem pre-dates A Boy's Will by a decade, and the oldest was written the year before he died. Because they were written over a span of nearly sixty years, there is no unifying theme or single contemporary influence. Instead, I have presented the poems in chronological order and provided introductory material as needed for each poem.

“Old Age” (1903)

The central character in this poem may have been based on Johnathan Eastman, the grandfather of Frost's close friend Carl Burrell. Burrell and Eastman lived with the Frost family and helped him work the farm until Eastman's death in 1902, a year before the poem was written. Frost's own grandfather, William Prescott Frost, died the same year. Those visiting the Frost farm in Derry may still see the simple attic room where Eastman stayed while living with the family ll. 19–24. He said “It's Specific Gravity” / “Do you mean by that that it's grave?” / … / Then I knew he didn't mean Seriousness / When he said Gravity: Specific gravity is the density of a substance relative to the density of water. Frost's use of this unusual technical term is intriguing. He may have learned the term in high school as part of an experimental laboratory course that was taught in the spring of his senior year at Lawrence High School. In an unsigned editorial from December of 1891 in his high school bulletin, Frost writes: “A class will commence in experimental physics, next term, a step forward or rather a mere turn in the right direction. We have to regret that the year is so far advanced before undertaking the task.”

Frost may also have learned about specific gravity as part of his farming duties, where specific gravity is used to characterize a variety of materials including minerals, sugar solutions, milk, and soil. Practical analytical methods for characterizing hens’ eggs based on specific gravity were published in the 1930s but may have been used by farmers before that.