The catapult on terra firma must be the one erected at the MSFU at Speke on July 6th 1941. The first one was erected at Farnborough by the Experimental Catapult Flight of the R.A.E. It was only suitable for Fulmars.
The man in charge of the Farnborough catapult was a Mr. Crowfoot, famous for his bowler hat, and he came too Speke to oversee the new catapult, along with Squadron Leader Louis Strange (DSO, MC, DFC from WW1 and 49 years old) who would subsequently run all launches at Speke. He was the first pilot to be launched from the Speke catapult. He landed to tell the assembled pilots
"If an old boy like me can do it,it won't mean a thing to lads like you."
The first launch was not without some problems. One account recorded that it was
"a great occasion which was witnessed by everyone who could possibly attend. Squadron Leader Strange did a magnificent launch in which the blast screen suffered severely, being partially stripped of its metal facing, the woodwork set on fire, and the whole being left in a shaky condition. After this exhibition of what the firing of the catapult could do in the way of blast, the screen was greatly strengthened."
Different times!
I suspect the photograph of the launch from a ship might have been taken in Canada. It was common practice for the aircraft to fly off at the end of a crossing. Initially they were craned off, then transported for maintenance, but flying off proved much quicker and more fun.
Cheers
Steve