Fixing clocks isn't as easy it seems; I remember my dad's disastrous attempt to fix my grandfather's old mantel clock. He forgot to release the tension in the main spring before trying to take it apart, which meant that at one critical point he removed a screw and the whole thing exploded, for want of a better term, stripping all the teeth off the main flywheel in the process. It cost a fortune to get put right by an expert afterwards (it would probably have made more sense to throw it away, but it has sentimental value.)
Anyway the chapel on Gray's Inn Lane was otherwise known as the Chapel of St Bartholomew and was destroyed in WWII. (Apparently it was quite a plain, flat-roofed building.) Wren's St. Mary's Abchurch on the other hand thankfully still survives, although like most of the Wren churches it was damaged in WWII also.
Is it just me, or are most of the suggestions for reducing cholera on that handbill largely irrelevant? I'm fairly sure that lack of sleep wasn't a known cause of cholera (And even if it was, it was something that most of the poor in those days had little choice over anyway.)