The Elephant Man (film) - what is this piece of equipment in the surgery?

Factual Questions
1

I’m unable to find a clip, so I’ll describe it:

Early in the movie, about 7 minutes in, we see Anthony Hopkins as Dr. Treves performing surgery on a man injured in some sort of machine accident. There’s another doctor operating along with Treves, a man at the patient’s head apparently administering ether, a young man at the foot of the operating table holding a rope in case the patient moves, and next to him is a man with a machine.

The machine seems to occasionally squirt a liquid. What does it for?

For those unfamiliar with the movie or the story of Joseph Merrick, it takes place in the late 1880s. The doctors are depicted as unmasked and there are bare flame fixtures, probably gas, illuminating the operating room. I’d really like to know what that mysterious device is.

2

Here’s the scene. It’s an antiseptic spray

3

Therefore, Lister tested the results of spraying instruments, surgical incisions, and dressings with a solution of carbolic acid. Lister found that the solution swabbed on wounds remarkably reduced the incidence of gangrene

4

Asked and answered - thank you!

5

Funny enough, the antiseptic mouthwash “Listerine” was named after the same Dr. Lister.

6

Lister had nothing to do with Listerine though it was apparently named in his honor or to cash in on his reputation.

The machine Lister invented to spray carbolic acid in the air around surgical patients (and used on Queen Victoria) was called the “donkey engine”.

https://www.npr.org/sections/health-shots/2017/10/13/557367840/the-butchering-art-how-a-19th-century-physician-made-surgery-safer

7

I always wondered about the anti-septic spray, so today I looked it up.

Lister was a clinical-research surgeon, with week theory but strong practice. On the numbers, he found that spraying phenol was not an effective part of his anti-septic practice. He tried it, it didn’t help, and he stopped doing it.