Yes, you can also chisel information into cave walls in a similar fashion. The novelty here is that the indented information can be "erased" by uncompressing/un

Yes, you can also chisel information into cave walls in a similar fashion. The novelty here is that the indented information can be "erased" by uncompressing/unsqueezing/removing external stresses from the sponge (or other cellular material), but while it is in the compressed/stressed (pseudo-plastic) state it can hold on to the impressions almost indefinitely.