interesting guys, and good to see such a wide spread of knowledge, although some interesting assumptions, many of which i might have
made before my studies.
interestingly, teak was not "technically known" until linneaus the younger reported it as a specific species in 1782, but i am sure that the asian locals used if before we knew about it. it is true that the gn specified a particular type of teak, but this is indeginous to northern india, and what became bangladesh, as well as burma.
the first recorded usage in a boat that came to england that i could find, was one built for the east india company in about 1812. At this time, because of the napoleonic wars, the admiralty still held a monopoly over hardwoods, even imported ones. but if as is suggested they preferred oak, then many of the other timbers would have, if cheap enough been used in other things.
although it is true that walter williams built the first carriages used on the gnr, whilst joseph wright, whose company became metropolitan, built carriages out of teak too. i can find no record of walter williams actually using teak in his road carriages, but am again, keen to be shown a source material. as for oak in gnr carriages, it was specified as american white oak. amazing what you can learn from a simple coach
paul