Had many a discussion with the late Duncan Williamson anent the "supper" bell being rung--he, having been told by some "expert" that this was an indoor bell rung by an indoor servant, refused to recognise the fact that many "Big Hooses", some directly employing upwards of forty people, in gardens, stables and home farms, usually had a large external bell, hung on a purpose made frame or convenient tree branch which was rung to let the workers know that it was yokin time [start of days work] or louwsin or supper time [finish of the, usually long, working day]
This was the practice in Scotland until the 1800s when many estates, the owners having made large fortunes from coal mining, slavery etc., had built magnificent home farm steadings which usually had an arched entrance to the close and having a large clock and bell in the turret above the arch.
Today, one can recognise the home farm of an estate by its architecture even if the "Big Hoose" be long gone.