The Blog (archived)

Category: Experiments

Hot Enough To Cook An Egg On A Sidewalk?

Sunday, January 17, 2010

Is there any truth in the phrase “hot enough to cook an egg on the sidewalk” (or the footpath as we call them in Australia)? I’ve often wondered this myself, and rather than just google it I thought it would be more interesting to try it and see the result with my own eyes.

An egg at varying stages of cooking on hot bricksThe main ingredient - a hot day - was clearly present. Outside my home I measured the temperature as 41°C (105.8°F) in the shade, although I suspect it may have been closer to 42.9°C (109.2°F) which was the official Perth maximum. Whichever it was, it certainly qualified as hot.

I don’t have a footpath nearby, but the top of a low brick wall provided a flat surface with similar thermal properties. As for the egg, an old one in the back of the fridge, a year past its use by date, was a perfect candidate. I could use it in an experiment without feeling I was wasting it.

Having cracked the egg on the bricks, I photographed it at intervals to record the changes (click on photos to see a larger version). The egg white stopped spreading out within a minute, and the yolk firmed noticeably within two. It looked hopeful! After a promising start, however, further progress was disappointing. Even after half an hour most of the whites were still gooey and not white.

When I eventually scraped the egg off the bricks after two hours, the whites were mostly firm but not properly cooked. The yolk looked almost edible, but as the egg was so old, not to mention contaminated by dirt and bits of brick, I didn’t fancy eating it. I concluded that hot bricks (equivalent to a sidewalk) are not a viable way of cooking an egg, even if you overlook practicalities like hygeine.

Back inside, I consulted the internet. According to the US Library of Congress, eggs need a temperature of at least 70°C (158°F) to properly cook. Also:

“Once you crack the egg onto the sidewalk, the egg cools the sidewalk slightly. Pavement of any kind is a poor conductor of heat, so lacking an additional heat source from below or from the side, the egg will not cook evenly.
Something closer to the conditions of a frying pan would be the hood of a car. Metal conducts heat better and gets hotter, so people actually have been able to cook an egg on a car hood’s surface.”

I couldn’t get a reliable temperature reading of the bricks, but suspect they weren’t hot enough. The roof of a car is a much better idea. Any car parked in the sun during a Perth summer can get up to 60°C (140°F) inside, and I’ve measured this in my own car often enough. The roof should be hotter, and with some aluminium foil and a little oil, I expect an egg would cook more effectively there than on brick … probably good enough to eat.

I’ll try egg-cooking on a car another time. For now I plan to stay in the only sensible environment in such hot weather - indoors.


The Cost Of A Healthy Meal

Saturday, February 21, 2009

“Healthy food costs too much” is a complaint I’ve heard many times on TV - usually on current affairs shows where people account for their over-indulgence in take-away and fast food. I’ve often thought the opposite was true, so after eating one of my favourite healthy dinners last night I thought I’d calculate the cost and see exactly how expensive it is, or isn’t.

The healthy dinner consisted of a selection of fresh vegetables … peeled, chopped, bathed in olive oil with a little garlic and ginger, then left in the oven to slowly roast for an hour. Sprinkled with a little salt and dried oregano, this substantial vege feast was not only bursting with goodness but also tasted great and filled me up. The smell was pretty good too. To drink with it, I had a chilled glass of water - filtered tapwater with a bit of lemon juice (from my own tree) which is refreshing and complemented the veges nicely. The cost of this drink was negligible; here is the cost breakdown of the meal:

A healthy roast vegetable dinner

0.65 sweet potato
0.70 butternut pumpkin
0.55 white gourmet potatoes
0.24 carrot
0.38 pickling onions
0.17 garlic, minced
0.14 ginger, minced
0.45 olive oil (extra virgin)
0.02 salt and dried oregano

This is cheap for a main course in Australia - I don’t know of any take-away fast food meal with drink which can be had for less than $3.30, or $4.30 if you add some yoghurt for dessert like I did. I haven’t got the time or inclination to do a thorough price survey, but I’d expect to pay two or three times that much, per person, for a typical burger combo meal, or fish & chips, chinese, take-away chicken, or pizza. Some good frozen or refrigerated dinners from supermarkets can be found for $4 to $6, which is probably the cheapest fast food option, but still not quite as cheap as a healthy dinner made at home.

But what about meat? I often eat fish or chicken, in which case I’d halve the amount of vegetables above and steam them in the microwave. The total cost would vary a lot, depending on what fish or chicken I used (I’ll take note of the costs in future), but would still be less than an equivalent take-away … and healthier!

I should point out that the ingredients I listed above were all top quality, fresh, and locally produced here in Western Australia. You could lower the cost even more by using lesser quality imported vegetables from supermarkets, although they don’t taste as good.

Next time I see someone on TV with a burger and fries, complaining that healthy food costs too much, I’ll feel justified in disagreeing. I suspect the only way that home-made healthy food costs more is if you measure the cost in terms of time, effort, and planning ahead, rather than money.


Review Of A Daylight Savings Boycott

Wednesday, April 9, 2008

Last October when Western Australia switched over to daylight saving, I refused to change my clocks, having decided to continue operating on standard time (see "In A Time Zone Of My Own"). Now that daylight saving has ended for this summer, I can look back and review how practical it is to live in your own personal time zone. In a nutshell - it worked for me, but wouldn’t be practical for everyone.

daylightsavingchange.gifI quickly became accustomed to adjusting the times in my head. For example, a 9:00am class began at 8:00am as far as I was concerned, and from my perspective the TV programs I watch began an hour early (mostly an advantage). The only time I got caught out was when I turned up at a shop 20 minutes before I thought it would close, to find it had closed 40 minutes earlier. Oh well, I was bound to forget at least once!

Most of the time, however, I was able to live by non-daylight-saving time without any problem. In fact, I became so used to it I still occasionally find myself looking at a clock and mentally noting what the time is for “normal people” - even though daylight saving has ended.

Whether this is feasible for others depends on how much one’s life interfaces with the outside world according to a schedule. For someone who lives by the clock, with many appointments, operating on a time different to everyone around you could be very confusing - and more trouble than it’s worth. But for those whose lifestyle is less regulated by the clock, living in your own individual time zone can indeed work smoothly, as I have discovered. If daylight saving becomes a regular occurrence in Western Australia, so will my boycotting of it.


In A Time Zone Of My Own

Monday, October 29, 2007

Australia’s summer time zones,
showing hours ahead of UT (GMT).
The unofficial red +8 zone only
applies to me and my home.

Is it possible for an individual to live according to standard time while everyone around him adopts daylight savings time? I’m not sure, but I’m going to find out.

Yesterday Western Australians put their clocks forward for the start of daylight saving. We don’t normally have it here in WA, but we are in the second year of a trial period before yet another referendum to see if daylight saving will be adopted permanently.

We’ve already had three trial periods followed by referendums, and have voted against daylight saving three times over three decades, but our politicians clearly don’t like the decisions of those they allegedly represent. Last year I blogged about it (see "Democracy in Western Australia?" for the full story).

If a majority of my fellow citizens had voted for daylight saving, I’d accept it and reluctantly conform. But they didn’t. I object to the undemocratic way the government is forcing the issue against the demonstrated wishes of its people, and I’m feeling a little recalcitrant.

Last year I adjusted my clocks (all 14 of them) but managed to remain in my standard-time routine. This year I’ve not changed any clocks at all. I’ve declared myself and my home “daylight saving free zones”, and continue to live according to Western Standard Time as far as possible.

Of course there willl need to be some adjustments where I interact with society around me. I’m a student, and my classes now start an hour earlier (by my watch). No problem - I won’t need to get up much earlier as I already allow spare time at the start of the day. The timetable changes caused by daylight saving will just rob me of that spare time in the coolest part of the day (making it daylight robbery, not daylight saving!). My life is relatively uncluttered by appointments, and I’m not currently working, so I don’t expect any great problems with being an hour behind everyone around me. Keeping the time that better suits me and the climate should offset any inconveniences.

How practical will it really be to operate in my own time zone? Will it make much difference to anything? I don’t know, but I’m giving it a go, and will blog about the outcome. It’s my own subtle protest against goverments who ask their citizens what they want then disregard their answers.

Update: After writing this, I saw a story in the West Australian newspaper (see “Protesters glad to be behind the times“) about a Murchison couple who are ignoring daylight saving, as they did last year too. It seems many others in rural WA are doing likewise, so I’m not alone.


Natural is not always better

Thursday, February 8, 2007

I have a chronic rash which requires ongoing treatment with a corticosteroid cream. These creams are potentially harmful if overused, and so I thought wouldn’t it be better to use a natural remedy?

In reading about tea tree oil I learned that this naturally occurring oil has anti-bacterial and anti-fungal properties which might work in treating my rash. There was only one way to find out - I started applying tea tree oil to the left portion of the affected area, while continuing to use the corticosteroid cream on the right side for comparison.

At first, the tea tree oil appeared to be just as effective as the cream in controlling the rash. After about two weeks, however, the rash on the left side flared up in a big way. Either the tea tree oil was not really effective, or else would it was causing a reaction of its own.

I turned to Google. Much reading led me to believe that I’m one of the special 1-2% who suffer allergic contact dermatitis in response to tea tree oil. A new deodorant I had been testing also contained small amounts of tea tree oil, and a mild rash was also developing under my armpits. Instead of treating a rash, this natural substance had caused a whole new rash of its own, an example of a when a natural remedy is clearly not better.

The question remains - on non-allergic people, can tea tree oil treat a chronic rash as well as a corticosteroid cream? As I am unable to test this, perhaps somebody else would like to try it out.


Anti-Perspirant: Regular Versus Aluminium-Free

Friday, February 2, 2007

You hear a lot these days about the dangers of aluminium; in particular its neurotoxicity and possible link with Alzheimer’s disease. While there is much debate over this issue, and you can’t believe everything you read on the Internet, I thought it might be wise to try an aluminium free antiperspirant … just in case.

My main concern was - do they work as well as regular antiperspirants? I’d like to be aluminium free, but I sweat a lot, and don’t want to stink! Obviously some sort of test was in order.

ttoap.jpgThe product I decided to try was an aluminium free sports antiperspirant from Thursday Plantation. It contains tea tree oil - an essential oil from the Australian tea tree which has anti-bacterial and anti-fungal properties (not to mention a pleasant but subtle smell). To make a proper comparison, I applied each morning this antiperspirant to the left armpit, and a regular antiperspirant to the right armpit. Over several weeks of summer weather I’ve been able to compare the sweatiness and aroma of both armpits, and come to a conclusion.

The result: the aluminium free antiperspirant works just as well as the regular aluminium-based version. At least that was my experience, using the Thursday Plantation product. So once I’ve used up the old stuff and completely switched to the new, my armpits will be free of both aluminium and stink.

Note: this is my own honest opinion; I receive nothing for speaking favourably
of Thursday Plantation products (but I wouldn’t mind if I did).


Increase in body temperature while eating lunch in a refrigerator

Wednesday, April 26, 2006

At work I often spend my lunch break inside a large walk-in refrigerator at 3 or 4 degrees (celcius) - not everyone’s cup of tea, but I like it. One day I wondered how this affects my core body temperature.

If I stayed in the fridge long enough, my body temperature would eventually fall. However, the fact that I don’t even start shivering suggested little or no drop in temperature. I recorded my body temperature over several weeks, and the results surprised me:

Mid morning: 36.4
Before fridge: 36.2
After fridge: 36.9
Mid afternoon: 36.1

The slight decrease through the day was contradicted by an average 0.7 degree rise during the half hour spent in the fridge. Actual temperatures varied slightly from day to day, but warming of my body while refrigerated remained consistent.

Why? I’m active in the hours before lunch, then I sit passively in a deck chair during lunch. I thought the reduced activity would have slowed my metabolism, even if the cold didn’t.
Something is stimulating my core body temperature. Is it the cold that boosts temperature in the core parts by transferring blood away from my chilled extremities? Is it the eating of lunch that boosts my metabolism, like throwing another log on the fire? Or is it both, and if so, which has most influence?

Further measurements - with and without eating, and in and out of the fridge - are on the agenda. Having come this far I feel compelled to uncover the full truth.