I discovered this long ago -- quite by accident -- deep in my college library and have always wanted to own a copy. It's the reflections of an Italian poet who lived around the time of Byron.
The dude was bleak. You thought Marcus Aurelius was bad? These are some of the most depressing little apercus you're ever gonna read.
Here's a sample of his irremediable blackness:
"Man is condemned either to consume his youth (which is the only time to store up fruit for the years to come and make provision for himself) without a purpose, or to waste it in procuring enjoyments for that part of his life in which he will no longer be capable of enjoyment." (p. 37)
In fact, this volume, consisting mainly of one such reflection after another, is so bleak it's almost comic. But, as Housman's Mithridates discovered, it can be salubrious in small doses.
The author's oft-anthologized poem, "The Broom," brings up the rear of this slim volume.
It may interest you to know that Leopardi, at least according to his blurb in "The Norton Anthology of Western Literature," is said to have studied so assiduously that he morphed into a nearly-blind hunchback (hence his gloom), eventually dying of despair.
This has long made me wonder if it really is medically possible not merely to study so much that you become a hunchback, but to actually die of despair. Sounds like his doctors were more familiar with poetry than they were with simple physiology.