Collier chose criminality because he believed he would not be taken seriously on his own merits, even though it was well known that he had been friends with Keats, his father had entertained Wordsworth and other luminaries at the family home, and he had tutored Singer and Knight to some extent in perfectly legitimate editorial method. Nevertheless, entrusted with valuable mss. and books, he forged names and signatures and commentary in an unconvincing secretary hand. His greatest crime was his interpolation of neo-seventeenth-century marginalia in the "Perkins Folio," a copy of F2, ruining it forever. He was discovered and excoriated. Oddly, the emendations he forged were good and tenable conjectures, and would have been acceptable in book form or as part of an edition under his own name, without the folderol travesty of "Tho. Perkins." He published four Shakespeare collections and the first is usually the one that scholars consult. Because his chicanery was so intertwined with his second and third editions, scholars often quote them because, like it or not, they are part of the textual history of the plays. Some later scholars adapted those emendations in their published editions. The fourth edition (1878) was advertised as a clean break from the past, though he sometimes defends "Perkins folio" materials.
Collier's third ed. (1858) was the first appearance of "The Phoenix and Turtle" as Shakespeare's in a modern ed. His fourth ed. (1878) was the first to include Edward III, The Two Noble Kinsmen, A Yorkshire Tragedy, and even Mucedorus as Shak's in a modern ed. He omits PhT, which he had printed as Shak /s tin 1858.
1842-44
COL1v1 (Tmp TGV MWW) COL1v2 (MM Err Ado LLL MND MV) COL1v3 (AYL Shr AWW TN WT) COL1v4 (Jn R2 1H4 2H4 H5) COL1v5 (123H6 R3 H8) COL1v6 (Tro Cor Tit Rom Tim) COL1v7 (JC Mac Ham Lr Oth) COL1v8 (Ant Cym Per VA Luc Son LC PP)
1853
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1858
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1878
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COL4v8 (YT Muc Ven Luc Son LC PP)
Univeristy of Delaware page on the Collier Controversy
Terry Gray's page on Collier
Reasons for a New Edition (1842)
Notes and Emendations to the Text of Shakespeare's Plays from Early Manuscript Corrections in a Copy of the Folio, 1632 (1853)