when cold the milk poured with a neat stream whereas after microwaving it sloshed all down the side of the jug.

Our household has had a very bad experience since buying a new washing machine several years ago. Previously all our towels were washed in the old washing machine and left to dry on a clothes-horse indoors or on a washing line in the garden and were always soft. As soon as we got the new machine they were always stiff and rough.

We tried many suggestions from the web without any improvement in towel softness.

e.g.

- Use no fabric softener

- Use water softener tablets

- Do several washes with no detergent or softener

- Try different detergents

- Try different wash temperatures

So at year end we bought a new budget-priced condenser tumble dryer. We washed 2 well used bath towels in the machine with the usual detergent and softener and 1400 rpm spin and put them in the tumble dryer (automatic, "cupboard dry" setting, no High Heat). They ran for 33 minutes drying followed by the automatic 10 min Cooling Cycle.  The towels were lovely and soft.

What does the tumble dryer do to the cotton to achieve this softness?

Some observations:

We live in a hard water area.

Old washing machine was hot and cold fill; current one is cold fill only.

Whilst towels were tumble drying there was quite a strong fragrance smell in the hot air from the outlet of the dryer. A smell that is not there when towels dry in the same room on a clothes-horse. Fabric softener evaporating, I suspect.

Wash was at 95 degreec C. - same as usual.

Towels tested were one 100% cotton budget brand (supermarket) and one 100% Egyptian cotton prestige brand (department store). Both were at least a year old.

Convention dictates reducing standard oven temperatures by 20°C when using a fan oven. This makes tolerable sense for moderate temperatures and cooking times but for slow cooking at low temperatures it appears to be illogical. The effect of more efficient fan-assisted heat transfer must become irrelevant after an hour or two, and if a recipe suggests 110°C then setting a fan oven to 90°C (below boiling point) could give very different results. Should we correct for this?

I have encountered a question while pouring myself a glass of room temperature soda, then adding icecubes to cool it down. Is there a direct duration to which icecubes cool liquids? or are there variables as well? Take an example of a soda at room temperature of 23.9 degrees celcius. In a glass with 225 mililiters. If four icecubes are deposited in the glass immediately after coming out of a freezer with a temperature of -5 degrees celcius, what is the approzimate cooling time, or are there still more variables involved?

When I buy asparagus and keep it too long small beads of liquid appear on the tips. Why does it seem to decay preferentially from the tips, and what is the composition of the liquid that appears there? More importantly, can I still eat the asparagus after the liquid starts to appear?

Tyler Keaton, Bolton, Lancashire, UK

I got a lava lamp for xmas, and plugged it in, and after a few minutes, wax towers appeared. (sorry about the picture quality, my phone was the closest camera.)

Clearly, the usual method of putting it on weighing scales won't work on earth because the balloon would float. I also don't think you could put it in a vacuum as, while the balloon wouldn't float, the vacuum would cause the balloon to expand and burst. (I think)

If there are a number of methods, which would be most accurate?

A few conditions

• You can't weigh a deflated balloon and assume the mass of the helium is negligible.
• No theoretical calculations of mass from data book values like density and atomic mass.   

Consumer Reports in the USA reported on Pyrex switching from Borosilicate glass to Soda Lime glass.  Soda lime glass is less resistant to thermal changes and there have been reports of Pyrex products shattering.  Consumer Reports made a number of suggestions on how to lessen the likelihood of a shard producing explosion including "preheat the oven".  Isn't this illogical?  Surely slowly heating glass is less likely to make it explode than taking a room temperature pie plate a poutting it in a 350f oven?