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Blue tit

Bird Table Blues

Friday, 14th December 2001, West Yorkshire

blue tit A GREAT TIT on the nut feeder is nearly as small as the Blue Tit that joins it, so small that until the blue tit came along we were wondering if it was a Coal Tit. A great tit great titis twice as heavy as a coal tit.

Our resident Blackbird 'White-tail' is trying out something new; he's attempting to use the seed feeder. He's a bit too large to comfortably perch on the plastic ring around the hopper so he stands on the top of a garden light holder next to the bird table. Unfortunately from here the seed feeder is tantalisingly just out of reach.

Leaf-like Rock

phylliteHere's an unusual rock, used as a decorative building stone. It's been used to make a kind of vertical crazy paving around the back door of a business, formerly a bar, on Little Westgate, Wakefield.

collision Phyllite, which means a 'leaf-like rock', is a metamorphic rock. It started life as muddy sediments but was transformed when it came under pressure at a time when fold-mountains were thrown up during a continental collision. It's not as smooth as slate and it isn't so re-mineralised as schist. Like these related rocks, it's the pressures of regional metamorphism rather than heat that have transformed it.

New platy minerals, such as micas, line up at right angles to the pressure. These form cleavage planes. Phyllite wouldn't normally be used as a building stone because of the risk that one of these cleavage planes would give under pressure. The surface of one of these cleavage plains often has a greasy feel.

Phyllites are often greenish but this example is brownish. Perhaps this is due to oxidisation of the minerals in it?next page

Richard Bell
Richard Bell,
wildlife illustrator

E-mail; 'richard@willowisland.co.uk'