S. W. Fallon (1817-1880) is known for the dictionaries of the Urdu language (which was also known as 'Hindustani' at that time) that he compiled. There are several Urdu-English and English -Urdu dictionaries to his credit. But his dictionary that has attracted much appreciation, and some criticism as well, is titled "A new Hindustani-English Dictionary" and subtitled "with illustrations from Hindustani literature and folk-lore". Published from Banaras in 1879, it has a rich and invaluable collection of Urdu words, phrases, proverbs and quotations from Urdu and Hindi literature. A specialty of the dictionary is the inclusion of words and expressions from Urdu's regional dialects and rustic vernaculars, a feature that most of Urdu lexicographers did not deem fit for inclusion. This paper evaluates some of the critical opinions about this dictionary of Fallon's in the light of the modern lexicographic principles. It also studies some off the interesting and rare words/phrases/ expressions that have made it to the dictionary and are rarely found in other Urdu dictionaries considered authentic.