Tarmacadam

Driving around Plymouth today, you can't help but notice all the potholes everywhere. In many places, the old cobbled roads underneath the tarmac are being revealed. Saltash Passage is one particular place where the cobbles are appearing and it's easy to imagine what the area must have once looked like when trams travelled towards the ferry taking passengers over to Saltash. Many people will think that tarmac is a relatively new thing but amazingly, tarred roads date back to the 8th century and appeared in Baghdad at the time. Tarmac as we know it today has been around since 1903. Patented by Edgar Purnell Hooley in 1901, some of the streets of Plymouth were tarmaced in the early 1900s including roads in Stonehouse which were paid for by the then Earl of Mount Edgcumbe. Previously, Macadam road surfaces were used from 1820 and invented by Scotsman, John Loudon MacAdam. He called the process, macadamisation. McAdam's road surfaces were ideal for horses and carriages but were dusty and eroded when it rained. Once motor transport was introduced, the roads couldn't cope and a new formula containing tar was used. Hooley's patent involved mechanically mixing tar and aggregate and this was prepared before it was put on the road surface and compressed using a steam roller. Today, cobbled streets and lovely paved footpaths are regularly tarmaced over much to the annoyance of people who prefer the streets as they are, a reminder of times gone by. It's amazing to think that this whole process isn't a new one and has been going on in Plymouth for well over 100 years.

The photo shows Bedford Street on the day that the circus came to town. No cobbled streets there, just a dusty old macadam road.