If I leave my jar of brown sugar standing overnight, the surface crystals will bind together and I will need a spoon to scrape and loosen them so I can pour the sugar out. What property of brown sugar causes the surface to bind together so quickly?

This photo was taken during the winter after I had salted my driveway that was subsequently rained on. Why there is a ring of non-frozen moisture around the frozen area that surrounds the larger crystals that were not washed away? Clive Wells.

If I leave my jar of brown sugar standing overnight, the surface crystals will bind together and I will need a spoon to scrape and loosen them so I can pour the sugar out. What property of brown sugar causes the surface to bind together so quickly?

Peter Franks, Sydney, New South Wales, Australia

I ahve just read about a company producing lingerie that claims to aid slimming. It  is apparently made from fabrics containing "Active Bio-Crystals that assist in the reduction of cellulite". Could this conceivably work? If so, how?

Elaine Pettifer, London, UK

This water was in a plastic sheet covering up a canoe, the water is around 10cm deep. What caused these crystals to form in this manner?

I saw the delicate, leaf-like ice crystals in the photo whilst snowboarding in France, they measured from 20 - 80mm and were incredibly fragile. The area they covered in the photo was about 20m2 but we saw other patches close by. The site was at about 1800m.

The ice structure pictured is 14cm long, it formed in a single night in this bird bath, and there is nothing above it that could have dripped to form a stalagmite. The triangular cross-section, and angle of lean also suggest that this did not form in the usual way for a stalagmite.

On the day before, the bowl was full of water and the temperature was a degree or two above freezing, overnight temperatures dropped to -2 C, skies were clear with no precipitation, the structure was fully formed the next morning.

I assume this is in fact an ice crystal, but how, and why, did it perform this gravity defying trick, and why don't we see such structures more often?

We heard that a bowl of Epsom salts placed near a microwave or TV reduces microwave emissions, and these cause the crystals to turn to powder over time. This sounds like an urban myth, but we tried it.

To our surprise, the salts turned to powder within a week or two. Why does this occur? Are microwaves really involved?

Arlene Dowling, Australia

(Image: grz3gorz, stock.xchng)