Boomhall, County Derry 

Bence-Jones, Mark. A Guide to Irish Country Houses (originally published as Burke’s Guide to Country Houses volume 1 Ireland by Burke’s Peerage Ltd. 1978); Revised edition 1988 Constable and Company Ltd, London.

p. 45. “(Alexander/IFR; and Caledon, E/PB; Maturin-Baird/LG1952; Cooke/IFR) The original Boom Hall belonged to Robert Alexander, elder brother of the wealthy “Nabob” James Alexander, 1^st Earl of Caledon. The house was so named because of being near where the boom of Derry was placed during the Siege. James Alexander built a new house here ca 1772 to the design of Michael Priestly, soon after returning from India, and before buying the estate of Caledon, Co Tyrone, which was to become his principal seat and from which he was to take his title. 
 
The house was built with cut stone; two storeys over a basement. 
 
It has a seven-bay entrance front, with a three-bay breakfront centre. 
 
A projecting porch was added later. 
 
The garden front has a three-sided bow and side elevation of five bays. 
 
The window surrounds have blocking, even in basement;  and blocked quoins. Moderately high roof, on cornice. Large cubical central hall. Sold 1840 to Daniel Baird, through whose daughter it passed to the Maturin-Bairds. Afterwards the seat of the Cooke family.” 

http://lordbelmontinnorthernireland.blogspot.com/2014/08/boom-hall.html