Many runways are asphaltic concrete—aggregate in a bitumen binder—which softens and melts under heat.
A few years ago birds began dying after landing on these lakes and getting slathered in bitumen.
mid-15c., from Latin bitumen "asphalt," probably, via Oscan or Umbrian, from Celtic *betu- "birch, birch resin" (cf. Gaulish betulla "birch," used by Pliny for the tree supposedly the source of bitumen).
Gen. 11:3, R.V., margin, rendered in the A.V. "slime"), a mineral pitch. With this the ark was pitched (6:14. See also Ex. 2:3.) (See SLIME.)