On 23/05/2011 14:28, Timothy Murphy wrote:
I would like to get a 1/2in plastic pipe (for watering)
under the 3ft 6in wide granite-slab pathway in my front-garden.

Is there any clever way of doing this?
I don't want to lift the slabs,
which I assume have been there for 150 years.

Assuming there is nothing else by way of mains services under it then
you should be able to dig down either side and effectively drill into
the sub soil with a say a 22mm x 1m long masonry drill. You will have to
undercut the edges slightly or just be brutal to get the last few inches
of length and might have to drive in a copper pipe as support if the
soil is sandy and prone to collapse. I'm on brick like solid clay.

Regards,
Martin Brown