From: The District Line (2006), by M.A.C. Horne:
“…The District was more successful with parcels. From the 1880s both the Met and District successfully carried parcels, though the District did not carry unaccompanied parcels and newspapers continuously and there was a pause from about 1896. The service was fully restored in November 1902, though it only lasted until 18th March 1905, killed by impending electrification. The parcels were dealt with mainly at station booking offices, but where traffic was heavy parcels offices were provided with dedicated porters who conveyed them to and from the trains where they were carried in brake compartments with the guard. From stations it is recorded delivery boys using tricycles delivered parcels to customers.
An awkward commodity was fish, quantities of which the Billingsgate fishmongers insisted in sending by train from Monument for local distribution. Although much of this went early in the day, it was an especially obnoxious commodity that left highly unpleasant and slippery evidence behind…”