Ron,
Belated thanks for your great contributions to this thread (and the other on merchant navy songs)! I will have to follow up and look for that clip of the "Round the world" program.
I initially sought out the book you recommend, but having found also the HINDUSTANEE NAVAL DICTIONARY (Roebuck) on line for free, found it to be quite good, too.

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For people reading this thread in general, just to clarify some language terminology and stuff...

"Hindustani" (sometimes spelled "Hindusthani" by English speakers) refers to what is more commonly referred to today as Hindi-Urdu. For convenience's sake, people tend to shorten it to either "Hindi" or "Urdu," although properly speaking, each of those has different nuances and, unfortunately, political connotations (e.g. the association with certain religious communities). Hindustani or Hindi-Urdu is used generally to speak, with a certain amount of desired ambiguity, of the link language of northern India/Pakistan, of which there are many dialects, but it is most based on the dialect of Delhi-- that emerged from the combination of native Hindi dialect with the Persian-oriented vocabulary and idioms of the elite Muslim ruling class...later promoted as a quasi-native administrative language by the British colonial administration.

Like any language, Hindi-Urdu has loan words from many languages, although that does not make it a 'combination' of languages. Most common loanwords are from English, from Arabic (usually coming through Persian, so not really from Arabic), and things like Portuguese and French (from way back when they first colonized parts of India). What the "shipboard Hindustani," "Laskari baat", or whatever has is jargon. The base of the language is Hindi, but the nautical and sea-life jargon is loaned from a number of languages of sailing nationalities. In addition, the grammar of the Hindi is simplified (wrong?) in some points, probably as the result of finding common ground between sailors for whom it is not a native language. For example, in Hindi ir any other Indian language, one has to modify their verbs and possessive prepositions to reflect gender, but in the Lascar Hindi, that irksome distinction could be ignored.

Gibb