describe this vessel in one line.
It was a boat light enough to be carried over arduous terrain, but robust enough to be used in extreme weather conditions.
Halkett boat
A Halkett boat is a type of lightweight inflatable boat designed by (1820–1885) during the 1840s. Halkett had long been interested in the difficulties of travelling in the Canadian Arctic, and the problems involved in designing boats light enough to be carried over arduous terrain, but robust enough to be used in extreme weather conditions.

who designed the halkett boat? UNANSWERABLE
wiki:18127534
Halkett boat [SEP] Introduction
Although widely praised by Canadian explorers, Halkett's designs had a limited market, and he was unable to persuade the Royal Navy that they would serve any useful purpose in general naval service. Efforts to market them as platforms for fishing and duck shooting failed, and they were commercially unsuccessful. Only two Halkett boats, that of Orcadian explorer John Rae, and one held in the Hudson's Bay Company Museum Collection at the Manitoba Museum are known to survive today.