Marble is a common building material, and what we have here is marble chips. I'm going to add some acidity here. About 10 times more acid than the most acid rain. But you can see immediately that the acid attacks the marble and starts to dissolve it.

It's not what you'd want in your cup of coffee, so Dr.Greg Ayers from Australia's science agency, CSIRO, is collecting samples of rain and measuring them for acidity.

Ph is measured from Zero to fourteen. On the alkaline side, seawater is around 8 and at the acidic end Orange juice and soft drinks are around PH2 or 3. Unpolluted rainwater should measure at around PH 5 and any measurement under 5 would be considered Acid Rain.

As Australia is sparsely populated, its cities are far apart and it has no neighbors, the readings are not very high. In areas where there are smelters and power stations however, the problem of acid rain is far greater.

The major effects are on forests and rivers and lakes, where the acid rain causes the soil or water to be so acidified that trees won't grow or in fact they can even die completely and rivers and lakes they can become so acidic that they won't support any sort of aquatic life.

CSIRO is working with Australian industry to help accurately and inexpensively track the spread and levels of acidic particles, before they become a health or environmental hazard.