  A lexical database tool tailored for phonological research is described.
Database fields include transcriptions, glosses and hyperlinks to speech files.
Database queries are expressed using HTML forms, and these permit regular
expression search on any combination of fields. Regular expressions are passed
directly to a Perl CGI program, enabling the full flexibility of Perl extended
regular expressions. The regular expression notation is extended to better
support phonological searches, such as search for minimal pairs. Search results
are presented in the form of HTML or LaTeX tables, where each cell is either a
number (representing frequency) or a designated subset of the fields. Tables
have up to four dimensions, with an elegant system for specifying which
fragments of which fields should be used for the row/column labels. The tool
offers several advantages over traditional methods of analysis: (i) it supports
a quantitative method of doing phonological research; (ii) it gives universal
access to the same set of informants; (iii) it enables other researchers to
hear the original speech data without having to rely on published
transcriptions; (iv) it makes the full power of regular expression search
available, and search results are full multimedia documents; and (v) it enables
the early refutation of false hypotheses, shortening the
analysis-hypothesis-test loop. A life-size application to an African tone
language (Dschang) is used for exemplification throughout the paper. The
database contains 2200 records, each with approximately 15 fields. Running on a
PC laptop with a stand-alone web server, the `Dschang HyperLexicon' has already
been used extensively in phonological fieldwork and analysis in Cameroon.
