A few days ago I started to write this and saved it but then, when I came back to finish off I could not find the draft. So I wrote it again. Then I managed to publish the draft which appeared suddenly, well anyway, in a general mess here.
But I am going to publish this too as it is part of the thinking together process and there is different information in both posts.
Ramble ramble ramble

So. Richard Keefe/Keeffe/O'Keefe ...etc ...... Miller?
It is most unfortunate that Cork is full of mills. There is a mill in every village and town. The place is full of fast, wild, waters that love to turn mill water wheels. In fact, Ireland is full of mills - paper mills, flour mills, tuck mills, linen mills, woollen mills, clay mills, industrial steam mills.......
What does "Miller" mean?
Windy Miller from Trumpton hauling sacks of flour?
A mill in Cork City?
Is Richard a Mill Owner or a mill manager?
Is he connected to a milling family? Does he work for the family firm? (John is educated = money and some kind of status or connection.)

Cork City has some mills on the River Lee. St Dominics Mill on an island ... mills at Cross Green. Nearby mills. On the Blackwater. Coachford. Clonmoyle.Brinny. Youghal.  Etc Etc. But every town has plenty of mills. It is like searching for a mill in a mill economy.

Is Richard a miller or as most wealthier millers were, also a merchant, corn, flour, animal feed, timber, earthenware, ...........
...... and there is also a ship connection. A seafaring tradition. Richard's son, our John, is reported to have some seamanship skills. Connections. Cork, Youghal, Wexford, Tralee, Ireland is full of ports exporting grain, butter, timber etc and importing coal.......

If you google enough you will find some notable Richard Keefe millers. Not in Cork City though. One family of Keefes were in Kildare at Rathangan and were a major maker of flour in 1782. They are recorded in Parliamentary Papers/Reports. Sadly in 1798 during a Rebellion,  British troops were quartered on them and the family lost so much feed and supplies that they were in debt and lost the mill. That is in Kildare.

There is a Richard Keefe miller in Rathmolyon (County Meath) in Griffiths Valuation with a mill that was so lacking in water power that it did not run for some of the year. This mill is
 lost.

A notable Richard Keefe was in Iffernock in the town of Trim in County Meath from 1845 ish to some time later..... a Richard who was celebrated for improvements in the processing of flour and who married into the Synott family of Waterford (merchants).

In Cork City we have a Keefe O'Keeffe at a mill on the river Lee and a Francis  Keefe probably connected and they have records around 1820 to 1840 for activities on the aforesaid river......well documented in various places..... St dominics Mill (distillery) and Crosses Green. Keefe has property on Main Street Cork (st Finbars) and there is actually a Richard Keefe in Main Street around the time of Griffiths Valuation.

At Brinny we have a John Keefe with a manager who was from Waterford and continues in the milling trade after the closure of the mill in Brinny.

There is a Helen Keefe who marries John Sherlock of Ballyquane Mills (Glanford Mills) and some documented history around this. They are connected to Woodville, Killshanig.

There is a Patrick Keefe at Ballyartella mills who has a lively history

And David Keefe with a clay mill, coal merchant, grain merchant, ship owner in Youghal with great connections and history around 1850 to 1870 .. connected to somewhere called Muckridge and so on so forth. His widow goes bankrupt around 1870 with the help of her son in law. One of the matriachal connections is Helen Troy,

Lastly we have a Richard Keefe of Rathronan Mills died 1852 and the mills...  later in the hands of a Mahoney and burnt down in 1880 something. Near to Clonmel and the burial place of William Smith O'Brien. Sentenced to be hung etc and then transported.

Notable, significant and recorded Richard Keefes are in Newmarket, Fermoy and Waterford. They are gentlemen, relieving officers, and so on.

And then there is Mooncoin.  Which has an extant mill and a history of Richard Keefes.

There is a John Keefe born 1838 in Ballymacoda Ladysbridge who was near a mill and near Youghal.