I double checked the 1894 directory section for Howth - and dont see anything for Warren Cottage or the surname Dave found (Thorburn), but there is something of interest in the index :
Wm. Thorburn, cement agent and concrete layer, 33
Dawson street - res . Warne [sic?] cottage, Howth
the other listings in the area, or which mention Warren or Balscadden, are :
Burrow
Miss E.J. Campell - Burrow national school
E.S. Lauder esq. - Caramore
Mr. James O'Connor
Kilrock Rd
Mrs. Kiernan - Balscadden cottages
George N. Ferguson esq JP - Balscadden
Sutton
Pierce Mahoney esq. - Warren Hse
Index
George Napier Ferguson, Balscadden, Howth; 48,Mountjoy-square
George N. Ferguson, esq. a. P. Balscadden, Kilrock rd. Howth
The two Thorburn entiries in the 1884 index are in Donnybrook and Blackrock.
The close listings in 1884 are :
Howth
Michael Noonan, Balscadden Ho.
Burrow
John Butler esq.
Edward Egan esq.
Mr. James O'Connor esq.
Sutton
Andrew Todd esq - Warren Hse
R.D. Kane - Warren Hse
not everyone is listed in Thom's.. especially those in cottages, or without a business or recognized trade etc
Shane