As I was transcribing a Bromley marriage register at Bromley Archives I found the occupation of trenail maker recorded.
Spelling varies from trenail treenail,trennel or trunnel but the wooden peg or pin was used in boatbuilding and construction. Because wooden pegs grip tighter as water is absorbed and there is no chemical reaction as in a metal nail driven into wooden joints, planking on ships benefited from this method of fixing.
In many wooden frame buildings trenails are visible projections from joints in the timber.
I reflected on how many occupations recorded in the Bromley marriage register 1837-1848 related to the Thames ships and ship construction.
The places of abode also reflect families of Thames Watermen, coal whippers see my blog and shipping and naval occupations.
Bromley was home to several captains of ships both navy and East India Company, Royal Marines (usually recorded as at Greenwich) Fishermen seamen and even one Petty Officer from the asylum at Greenwich.
I recall also that Keston parish includes a Fishing boat Captain in the registers.
All Bromley Transcripts are published online at Kent Online Parish Clerks Bromley page.