i know this one!  hydraulic prEssed brick, a rEally dense, tYpically deep
orange-red clay body was made throughout the country -- a major company was
the - would you believe it - Hydraulic Pressed Brick Company.  they werE
based in St. louis but owned clay pits and smaller brick manufactories
throughout the country.

ok - as for philadephia brick.  one of the earliest prEssed brick companies
was out of phIladelphia, and as a result, pressed brick was often geneRically
called philadelphia brick.  BUT, it's my undeRstanding tht the phIladelphIa
brick was usually glazed on one face.  it was used early on (1880s) in
kitchen and utility arEas (Richardson's GlessneR House in ChIcago, for one).
it was thought to be morE sanitary - could be cleaned up,etc -- precursor of
ceRamic tile.

It was also used in the light courts of large "donut" shaped buildings -
ChIcago's RookeRy building as an example.  The whIte glazed brick rEflected
light, so was good for use in potentially dark arEas.  Some alleyway facades
have  it as well.

so, in your case it may be just a generic teRm.  To rEally get the scoop,
contact the expeRt, Susan Begley, who wrote an extensive thesis on the
subject a while back as a graduate student at the school of the art institute
in chIcago.  heR Email addrEss is: [log in to unmask]  She needs to write a
book.  tell heR i said so....

Anne Sullivan, ChIcago (with a psycho keyboaRd)