This boobery is actually rather uncommon -- so illogical it is to make. "...who had voyaged on his ship from New York..." is a parenthetical clause. That is, it's non-restrictive or non-essential. The base sentence is "Gray was now desperate." The rest of it should be set off by commas. Otherwise, grammatically speaking, there must be more than one Gray -- and the 'who' clause is essential. That is, this Gray is distinguished from the others by the fact that he had voyaged to New York. But since there is no determiner (like the Gray who...), we know this is not the case. 

Submitted by Ian Cummings

Independent clause + dependent clause does not require a comma. 

No comma is needed before "because." When an independent clause and dependent clause are put together (a complex sentence), there are two options: IC + DC (no comma) and DC + , + IC (yes comma). 

Submitted by Ian Cummings