odd wall material in Victorian home

[radish]

This is my first post, so I'm sorry if this has been covered before, but I haven't been able to find any information on this anywhere else on line.

I just moved into an old Victorian apartment. I want to hang some pictures and put some shelving units up on the walls. Every time I drive a nail into the wall it goes about halfway through, then stops. It hits something really spongy and weird on the other side, and some soot colored dust comes sprinkling out of the hole. I can't get the nail to go through straight since this material isn't firm.

Does anyone have any experience with this? I'm not really sure how I should deal with this stuff, since I'm renting I don't want to do anything that's going to make gigantic holes. Thanks a lot!

[HayZee518]

those victorian houses were at their time the "piece de resistance" - their walls were plaster on top of a screen type lath. other houses used plaster with horse hair as a binder on top of wooden lath. the lath - either wood or metal was nailed up against 2x4 or 2x3 studs mostly 24" on center. it might be easier for you to, instead of nailing something on the wall, use that new fangled hanging system where you pull off a release paper and just stick the hook up on the wall and hang whatever you want on the hook. it's made by 3-M company and I can't think of the product name.
it's called 3-M Command strips.

[radish]

Thanks a lot for the advice!