These entries are drawn from A Collection of Gaelic Proverbs and Familiar Phrases, edited by Alexander Nicolson (1881), itself an expansion of Donald Macintosh's original 1785 collection — one of the largest published collections of Gaelic proverbs, running to nearly 4,000 entries across 480 pages. This page is a selection, not the whole book: around three dozen entries chosen for being clear, well-preserved in the scan, and representative of what's here. The book is public domain, digitised by the National Library of Scotland via archive.org.
Where the original book notes a parallel Scots, English, or other-language saying alongside a Gaelic one, that's included in the card as a note.