The Recovery of Gaius' Institutes
The complete work was
unknown except for excerpts in Justinian's Digest, 
until in 
1816, 
B.G. 
Niebuhr discovered 
a manuscript in the Cathedral Chapter
Library of Verona, in 
which some of the works of Saint Jerome were written 
on top of an earlier text, 
which proved to be the lost work of Gaius. The greater part of the
palimpsest has been deciphered, and 
the text is now fairly complete. More recently, two sets of 
papyrus fragments have 
been found.
The 
discovery of Gaius' work has thrown light on portions of the history 
of Roman law which had previously been obscure. Much of the historical 
information given by Gaius is absent in the compilations of Justinian, and, in 
particular, Justinian's jurists did not put Gaius' account of the ancient forms of procedure in actions 
in the Digest. In these procedure 
forms can be traced the "survivals" from the most primitive times, which provide comparative law with valuable illustrations, 
and which may explain the 
strange forms of legal procedure found in other early systems.
There are several editions of the Institutes, beginning with the editio princeps of I.F.L. Göschen (Berlin, 1820). The author of the 1911 Encyclopaedia Britannica recommends the English edition of Edward Poste published in 1885,which includes an English translation and copious commentary; more recent editions include E. Seckel-B. Keubler (8th edition; Leipzig, 1939), and Francis de Zulueta, with an English translation and commentary (2 volumes; Oxford, 1946).