What are/were India Rubbers?

[WitBeyondMeasure]

I'm reading What Katy Did as part of my literary nostalgia trip and it refers several times to the children wearing India Rubbers. I've googled and come up with nothing likely so I'm wondering if anybody knows?
Sometimes the context makes me think they are wellies, sometimes I think it could be a rain coat or maybe something that goes inside a shoe..

Please enlighten me!

Galoshes, I think. Sort of overshoes.

It was a natural rubber substance from a plant, which could be used to make a fabric. It was used to cover baseballs, and I think maybe for waterproof jackets?

God, I reread this a few years ago for the first time since I was about nine. I’d completely forgotten ghastly Cousin Helen and her School of Pain.

I don't know for certain, but I assumed that they were waterproof coats. I'm sure I've heard of India rubbers in other old books but off hand I can't remember which.

I have an idea that wellies are called 'rubbers' in some parts of the world, so maybe it means that.

waterproofs

How weird I’ve not read this since my childhood but picked it up again tonight

Rubbers or pencil erasers as far as I know

Week that is what my granny always called them ..

@user1486076969 thanks for that! Like a rubber poncho

@Gimmeesugar how strange!! I was on kindle store earlier and picked up the four part collection for 49p! I knew about what Katy did and what Katy did next but had no idea about another two!