This could be an illustration for The Hobbit, but in fact it’s one from my book Beowulf and the Dragon. The scene does look and read somewhat familiar, though …
”[…]se ðe on heaum hæþe hord beweotode, stanbeorh steapne; stig under læg eldum uncuð. Þær on innan giong niðða nathwylc, se ðe neh gefealg hæðnum horde, hond wæge nam, sid, since fah; ne he þæt syððan bemað, þeah ðe he slæpende besyred wurde þeofes cræfte; þæt sie ðiod onfand, bigfolc beorna, þæt he gebolgen wæs.”
(original Old English text of Beowulf)
“On a high heath, he guarded treasure in a steep stone barrow, below which lay a secret passage. Some man had found his way inside, crept close to the heathen hoard, and stolen a large, jewelled drinking-cup. The dragon was not shy to show he had been tricked in his sleep by a thief’s guile; the men of the region quickly felt his rage.”
(verse translation by John Porter)
I wish they’d publish Tolkien’s own translation of Beowulf which still lurks somewhere in the archives. The drawing was done in charcoal and red chalk.