Thanks for your reply. I was guessing some time in the 20s judging by the hats being worn by some of the ladies in the rowing boats. My guess is that this shows the aftermath of a race... and perhaps not a very successful one so I wonder if that is why it never caught on in Dartmouth... but that is ...

Hello all, I don't know much about classic power boats but have found this among the family photos. I'm pretty sure that the location is Dartmouth because that is where the family lived. The larger vessel on the left is an Admiralty Harbour Service Launch, likely one of two based at Britannia Royal ...