this from 1881 census could be your family - Leonard is very unusual for Manx as a given name
Lonan No 10 Stoney Road CLAGUE John P. Head M M 37 Lead Miner born Lonan IoM
Lonan No 10 Stoney Road CLAGUE Euphemia Wife M F 32 Miners Wife Lonan IoM
Lonan No 10 Stoney Road CLAGUE Euphemia Daur U F 14 Miners Daur Lonan IoM
Lonan No 10 Stoney Road CLAGUE Sarah E. Daur U F 12 Schooler Lonan IoM
Lonan No 10 Stoney Road CLAGUE John L. Son - M 6 Schooler Lonan IoM
Lonan No 10 Stoney Road CLAGUE Lewis H. Son - M 3 --- Lonan IoM
Lonan No 10 Stoney Road CLAGUE Lydea S. Daur - F 1 --- Lonan IoM

on my emigration page http://www.ee.surrey.ac.uk/Contrib/manx/famhist/genealgy/emig.htm
is
South Africa
A number of Manx emigrated to South Africa. In the Manx Church Magazine for March 1895 under notice for Foxdale is found:

A letter has been received from Mr Philip Crellin, Johannesburg, South Africa, enclosing a draft for the sum of £19 l0s for Mrs William Henry Cain. This amount has been handed to her, and was most thankfully accepted. The following is an extract from the letter and the list of subscriptions:-We were very sorry to hear of the death of William Cain, and amongst some of us Manxmen on the estate and other adjoining properties we thought it our duty to subscribe what we could between us, and we have gathered the sum of £12 1s, and hand it over to you, and you can dispose of it to the widow as you think proper: - -Philip Crellin, William Radcliffe, John Quilliam, John Woods, Louis Crellin, Robert Corkill, Walter Corkill, Reginald Kitto, John M. Faragher, R. Skelly, £1 each; James Quayle, Robert Kelly, John Clague and Son, 10s each; Benjamin Wallis, 6s; Edward Quilliam, Thomas Faragher. William Clague, 5s. each