The reflective stuff in traffic lines is (or was) diatomaceous earth.
Diatoms are tiny planktonic creatures (I guess that means they don't have
sex) and their fossil remains are what is used in the paint. Or perhaps a
synthetic material is now used instead. I think reflective stripes were
first used in the 1920s as clained by Wayne County. I have an old book, the
State of Maryland highway department annual for 1928, which also shows
that, to compensate for the low level of street lighting and its total
absence on rural roads, and the low-powered headlights of the time (21
candlepower, though I can attest they are adequate on a really dark, unlit
road), it was customary to paint everything at the roadside white up to
about 4 feet off the ground--not only fences but buildings, tree trunks,
masonite cows, etc. This sort of thing shows how difficult 'recreating' the
past can be, as for movies and such. Too much has changed and been
forgotten. The roads of the pre-auto era or the first few automotive
decades are unlike anything to be found today in most places. 

Great Pumpkin (visible in all lighting situations)