The image of the rockets in the boats is credited to Captain W. Hyde Parker on the NMM site (see post earlier in thread). Maybe he did the others as well? Maybe you can email the NMM to find out?
Susan, good timing. Congreve’s "Treatise…" arrived on microfiche yesterday at my local library. There is no indication of any artist or source for this or any image shown.
Illustrations are listed in the Table of Contents but no attribution appears there, nor with the image, nor with the text on pages 83-84 that refer to this particular image, indicated only as Plate 12, figures 1-4. ("The Use of Rockets in Fire Ships, and the Mode of Fitting Any Other Ship for the Discharge of Rockets").
I found it telling that the image you referenced, titled "The Use of Rockets from Boats," appears as Plate 11 but the image is nowhere identified in the "Treatise…" as being created by Capt. W. Hyde Parker, 1814.
The "Treatise…" is about 80 pages long and appears to be more of a report or justification/propaganda rather than a scholarly effort so the lack of attribution might be easily explained.
I went to the NMM website and searched for the image I am interested in using first "Congreve," then individual word searches for rocket, rockets, fireship, fire ship, and found only the "Boats" image by Parker. I had done this before, but I was hoping that something new had been added since I began my search. No such luck.
NMM states that they do not do research (they recommend firms who do) so without the image already being in their collection, I somehow doubt that anyone could or would respond. Assuming otherwise, to whom or what department do you recommend I direct my question? I assume I would have to attach a copy of the image from the internet to make clear what I am looking for, plus the "Treatise" information.