losing gravel

Put the summary of the bug you're having here

What I expected to happen was...:
Describe what you thought should happen here

What actually happened was...:
Describe what happened here

Steps to Reproduce:
1. mine stone straight down
2. place torch 2 blocks above ground
3. go to top and place gravel and let it fall
4. once the two blocks without (on bottom) torch have gravel drop more you notice that the gravel disappear when they hit a torch they dont stack ontop of torch they disappear and you lose you gravel