English language
Free to read here, from Project Gutenberg.
Chambers's Twentieth Century Dictionary (part 1 of 4: A-D)
Roget's Thesaurus of English Words and Phrases
The Elements of Style
Diccionario Ingles-Español-Tagalog
Webster's Unabridged Dictionary
A Concise Anglo-Saxon Dictionary
The Devil's Dictionary
Hobson-Jobson
Putnam's word book
The Comic English Grammar: A New And Facetious Introduction To The English Tongue
A Concise Dictionary of Middle English from A.D. 1150 to 1580
Roget's Thesaurus
A Complete Dictionary of Synonyms and Antonyms
The Grammar of English Grammars
A Dictionary of Slang, Cant, and Vulgar Words
Stories from Tagore
The Gutenberg Webster's Unabridged Dictionary: Section T, U, V, and W
1811 Dictionary of the Vulgar Tongue
Chambers's Twentieth Century Dictionary (part 3 of 4: N-R)
The slang dictionary
An Advanced English Grammar with Exercises
The Gutenberg Webster's Unabridged Dictionary: Section I, J, K, and L
Fiue hundred pointes of good husbandrie
The Gutenberg Webster's Unabridged Dictionary: Section A and B
Phrases and Names, Their Origins and Meanings
A short introduction to English grammar
The Gutenberg Webster's Unabridged Dictionary: Section P and Q
The Raven, and The Philosophy of Composition
Chambers's Twentieth Century Dictionary (part 2 of 4: E-M)
The Gutenberg Webster's Unabridged Dictionary: Section S
The Gutenberg Webster's Unabridged Dictionary: Section R
English Past and Present
The American Language
Grammar-land; Or, Grammar in Fun for the Children of Schoolroom-shire
German composition
Reliques of Ancient English Poetry, Volume 1 (of 3)
Business English: A Practice Book
A Military Dictionary and Gazetteer
Fifteen Thousand Useful Phrases
An English Grammar
The Gutenberg Webster's Unabridged Dictionary: Section F, G and H
The Gutenberg Webster's Unabridged Dictionary: Section D and E
Heath's French and English dictionary
The Gutenberg Webster's Unabridged Dictionary: Section M, N, and O
Chambers's Twentieth Century Dictionary (part 4 of 4: S-Z and supplements)
Synonyms and antonyms
The Gutenberg Webster's Unabridged Dictionary: Section C