"The Natural Philosopher" wrote in message
...
Jon
Some of the roads where I lived as a child were tarred and then rolled
with gravel. Hurts when falling off bike.

all the roads here are done like that

Nowadays in the UK there are two types of road surface:

- tarmac - tar/stones pre-mixed, laid on the surface like icing and then
rolled flat

- surface dressing (what Jon describes) - tar sprayed on road, stones tipped
on top, cars left to roll them into the tar

Surface dressing would be fine if they would only use a road roller to roll
the stones into the tar, with any loose stones after that being "hoovered
up". But instead they think it is acceptable to impose very lower speed
limits (eg 20 mph on a 60 mph road) for several weeks afterwards while cars
roll some of the stones in, with the remainder being a skid hazard (hence
the draconian speed limit) until they get thrown onto the verge. Also, the
road tends to develop bald patches where all the tyres run, so they process
has to be repeated every few years.