Look beneath the lampshade
Ask to see the ceramic base without a shade hiding its neck and fitting. Measure the body, its widest point and the footprint on the furniture. Consider how the final shade will affect the balance of the whole object. The height of the base alone does not tell you the finished height of the lamp.
Document alterations
Photograph the cable entry, underside and neck. A hole may belong to the original construction or a later conversion; ask what is known. A repair near a mounting point needs examination before further tightening or dismantling. The names S. Letessier and René Meynial occurred in the former address, but their role for a particular object is not established here.
Build a complete lighting proposal
Provide the intended shade dimensions and furniture height to the person assessing the fitting. Have the electrical equipment and mounting arrangement checked before use. For two bedside tables, compare the finished height on each side rather than buying two visually similar bases in isolation. Keep a record of the chosen combination to guide any subsequent sourcing.
For the next part of your selection, read Antique chandeliers: measure before you buy.