The pictures on this page show a number of early-model (1940s to early 1950s) Model L5s. The first example, shown at the top of the page, had a distinctly old-fashioned pattern of bed (the section beneath the gap swoops down to retain strength), and a plain-bearing headstock with a domed headstock cover that  reached right down to the centreline of the bearings and, instead of being bolted in place, simply rested in its recess. Although this design of cover was necessary to allow the headstock bearing bolts to be undone one might imagine that if oil instead of an oil-and-grease mixture was used for lubrication leaks would have been a serious problem. The clutch was operated by a long horizontal rod that ran the length of the bed and was connected through a clevis pin on the headstock whilst sliding through a guide, supported on a tall bracket, at the tailstock end of the bed (although the fitting was not shown in all publicity pictures). The very first models had enormous (non-zeroing) micrometer dials, cheaply and effectively achieved by engraving the division marks into the flat rims of the cross and top-slide handwheels. Stalks extending from slides' end brackets reached up to the inner edge of each handwheel to provide a flat surface into which a zero mark was engraved.  Later machines, probably from 1948, were fitted with Timken roller bearings in a much more rigid, box-form headstock that also allowed the fitting of a conventional, bolt-on, shallow headstock top covert that guaranteed better oil tightness. At around the same time conventional satin-chrome zeroing micrometer dials were fitted; these were  of decent size and fitted with a thin knurled ridge to aid changes of setting by oily fingers. This second version of the lathe can be distinguished from subsequent models by full-circle (but non-engraved) handwheels a spring-loaded, bronze-lever, power-feed engagement handle on the apron and a bolt-on cast-aluminium changewheel guard.
The stands on early machines were, instead of being fabricated from heavy sheet steel (as on all later versions) either full length and made of cast iron or, more commonly, with a box-section cast-iron plinth under the headstock end of the bed and a simple leg under the tailstock. At the back of the headstock support was a pair of cast-in motor-mounting brackets in the form of long vertical T slots; however, these were soon abandoned and replaced by adjustable bolt-on mounts with pusher screws that made the fitting of different motors and the setting of belt tension a far easier task.
Besides the geared-headstock models Harrison also made, to meet a demand from factories equipped with overhead line shafting,  batches of machines with open flat-belt drive "cone" headstocks.
More pictures of a very early L5 can be seen here..