What is this pipe for?

Could anyone identify the pipe circled in red in the images below?

I moved into a Victorian terraced house (from 1870); I only have electricity and intend on getting gas installed, and came across this pipe which is not the current water supply (which is supplied from a separate lead pipe).

This pipe comes from the front of the house (same place where the water comes from) and cross half of the house, until it comes up through the floorboards and then it is capped.

I noticed another smaller pipe (circled in blue), which seems to be a distribution pipe. I am guessing there might have been a device connected between those 2 parts (may be a meter...). The guy from Scottish Water did not think it had anything to do with water, may be an oil pipe.

What are your thoughts? I am a bit wary of unscrewing the cap in case something burst out and cannot close it again. Any way I can find what it is for?

Basically I would like to decommission it in order to make place for the gas pipe.

An old gas pipe.

Do you think it could still be live? Though there is no record of any gas supply at my address when checking from https://www.findmysupplier.energy/

A bloke I know bought an old Victorian house with a gas pipe but no meter and just tapped into it for 'free' (eg stolen) gas for 15 years. It was recently compulsory purchased as it was on the route of the new Thames crossing and everything had to be working so he had a calor/propane gas boiler fitted (or had his one converted, can’t remember which) and left just a gas bottle when he moved out. He was paid nearly £1m for it and moaned when the purchase was delayed a few weeks because he had to buy another bottle of gas!

It is an old gas service pipe

ianmcd said:

It is an old gas service pipe

Click to expand...

The underground part of our gas supply was in rotting steel pipe, like that, until around 6 years ago. The section inside our property was changed to modern plastic 40 years ago. The old pipes leaked and released gas into the ground, at the rear of the properties, so every so often, they would come round with gas leakage detectors. More and more frequently as time passed, until the replaced them all with plastic run along the street at the front.

The oily rag was an old plumbers trick to seal off non live pipes !

The oily rag you see is denso tape.