<p>Rubber sheet undergone drying in smoke. Two versions are there in the picture.
1. Fresh sheet.
</p>
2. Dried in smoke.
<a href="//commons.wikimedia.org/wiki/User:Vaikoovery" title="User:Vaikoovery">Vaikoovery</a>
CC BY 3.0
<span class="int-own-work" lang="en">Own work</span>