The Only Constant Of Anything Is Uncertainty

I didn’t plan on doing it. It just happened. I haven’t seen it as a meme on any social media sites so I think I must be the only person doing it. I find myself stopping and counting the number of avocados piled onto a display shelf, and I’ll try to guess the number of avocados that are prepacked in the small, green mesh bags whenever I’m in the produce section of a supermarket. Not all that long ago, you’d only see avocados in the Omaha shops in summer; you might buy a couple to mix with a packet of guacamole seasoning mix to make some fresh dip. But now it seems avocados anchor the produce section year round in all of the local supermarkets; it appears that Omahans have fallen in love with the little green fruit.

image source:jmcadam

I don’t know how Australia started the avocado toast craze in the US; but a lot of thanks needs to go to those down under, prawn barbecuing maniacs. A couple of small franchise chain restaurant serving only breakfast, brunch, and lunch have sprung up in the neighbourhood; avocado toast is featured on their menu. Now it’s a bit of a stretch to compare them to a Melbourne cafe; a coffee shop with friendly staff, creative food, creative food, and a good neighbourhood vibe, but they are neighbourhood restaurants, and they do serve avocado toast. One of the restaurant offers whole grain toast topped with fresh smashed avocado, EVOO, a lemon wedge, and Maldon sea salt served with two basted eggs; and the other serves smashed avocado lightly seasoned, spread across a toasted wheat bread, topped with a sliced hard boiled egg, and a sprinkle of chives and pepper flakes. I grew up with Vegemite on toast in the morning so I haven’t gone the whole nine yards with the smashed avo on toast thing, but I do applaud Omahans obsession with avocado toast, and the convenience of being able to buy an avocado year round. Maybe it’s time to try out Vegemite and avocado on toast.

image source:jmcadam

Whenever I count how many avocados are prepacked in a small green mesh bag I always end up with the same number; regardless of what time of day, what day of the week, or what supermarket I’m counting in. I’ve started to vary the time, and the day, when I nick into the produce section to count the avocados; I don’t want to be so predicable that the avocados know when I’m coming to count them. Arriving at the same number every time I counted the avocados, reminded me of Avagadros number; I started started referring to the number of avocados in a green mesh bag as the Avocados Constant. It must have been during my first year at Footscray Technical College when I first heard about Avagadro’s number; most likely in Physical Chemistry. I don’t think it was anything I copied off Mr Fraser’s blackboard at Williamstown Tech. Willy Tech’s three science classrooms stretched down one side of the main corridors; and were separated from each other by a small equipment and supplies storage room. Mr Fraser taught fourth form science in the middle room. The room was configured with four long lab benches, with gas taps for bunsen burners, running across the width of the room, and a long lab bench along each of the two side walls; they housed sinks with curved water taps, and extra gas taps for bunsen burners.


4AB was timetabled as a double section for science classes so we sat ten to a bench, facing the front in a straight line, on lab stools. Mr Fraser taught the science topics in the sequence prescribed by the Victorian Education Department’s statewide, technical school science syllabus. Most of the time Mr Fraser, with his back to the class, would fill the front blackboards with chalk written chemistry, physics, meteorology, and geography definitions, descriptions, theories, postulates, and laws. When the statewide syllabus prescribed a demonstration Mr Fraser would oblige; during a physics class he assembled an intricate system of pulleys and levers on his front science desk, and choose two volunteers to step up to the front of the room to measure with a spring balance, and his blackboard ruler, whatever he pointed to as he changed the weights on his pulley machine. Mr Fraser wrote the observations and measurements on the board, substituted them into formulas, and we copied all of his calculations and conclusions from the pulley machine demonstration into our exercise books; but we couldn’t copy his excitement when he pointed to his calculations and announced we had determined the velocity ratio, and mechanical advantage, of a simple machine.


One time during a chemistry class Mr Fraser passed different elements and compounds to Max Fitzgibbon in the font row and told him to pass them along; telling the class to touch and feel them, and smell them. I remember touching and feeling mercury; it rolled easily in the palm of your hand, and when you dropped it onto the bench it divided itself into droplets that transformed back into one large droplet when you pushed them into each other. And the class shared together the exaggerated coughing and giggling as we took deep whiffs of Hydrogen Sulphide.

When the statewide syllabus prescribed a student experiment Mr Fraser would divide the class into small groups. Titrating to neutralise an acid was a prescribed class experiment for chemistry. It was books away and bags on the floor. There was probably five stations on each lab bench, and each group of three students had their own titration experiment. Mr Fraser demonstrated the use of a burette and pipette. We practised pipetting with water; then accompanied by with dire warnings from Mr Fraser about the hazards of acids and bases, the dangerous liquids were passed out to each group. It was the days before protective eye ware and suction bulbs, and we all felt a sense of excitement and risk. I think I enjoyed the thrill of putting a pipette into my mouth and sucking up acid into the pipette bowl; and then to just above the graduated marking on the stem.


We tried hard to be successful pipetters, but it was a challenge to slide your small index fingers into your mouth and then onto the top of the pipette stem whilst keeping the acid in the pipette above the marking on the stem. When you took the pipette out of your mouth you’d move your finger, to vary the air pressure, causing the liquid to drip from the pipette, until the meniscus was level with the graduated mark. It took several times sucking the acid into the pipette before we did a successful pipetting. Mr Fraser’s warning continually echoed through the classroom

watch out for air bubbles, and don’t suck to hard.

And for years after, whenever I stopped at a milk bar for a cold Tarax or Passiona, and took thr first deep suck on the straw I heard Mr Fraser’s warnings. I didn’t lose interest in using a straw to drink out of a glass or bottle until my first year at Footscray Technical College. The watering holes along Nicholson Street served 7oz glasses in the public bar without a straw; and that encouraged me to become disenchanted with the meniscus. I no longer cared if it was concave or convex.


Chemistry at Footscray didn’t possess the same wonderment or magic as Mr Fraser’s chemistry classes; but it was as mysterious. Within a short time, it was obvious that Mr Fraser had protected us from the complexities, and confusions, of Analytical Chemistry, Inorganic Chemistry, Physical Chemistry, and Organic Chemistry. Nowhere was this more evident than when the ionic bonding theories and molecular orbital properties of elements were introduced; painstakingly by lecture and discourse instead of passing mercury, and other elements around for the class to play with. And it seemed that every week in Physical Chemistry a new obscure constant, uncertainty principle, and equation was unveiled. We committed to memory: The Bohr radius (the average radius of the orbit of an electron around the nucleus of a hydrogen atom at its ground state), The Faraday constant (the amount of electric charge carried by Avogadro’s number of electrons), Heisenberg’s uncertainty principle (the position, and the velocity of an object cannot both be measured exactly at the same time), and Avagadro’s number (the number of elementary particles such as molecules, atoms, compounds, etc. per mole of a substance).

I grew fond of Heisenberg’s uncertainty principle and Avagadro’s number. After my final year at Footscray Technical College I practised, and refined the concept of the uncertainty principle. It was the late sixties and early seventies; an ideal time to embrace the concept of an uncertainty principle. As I searched for inspiration and idealism in the ordinary I mused over whether there was a thought experiment that would allow one to deduce Heisenberg’s uncertainty principle instead of observing it. And Avagadro’s number was my grappling iron to actuality; I knew that something would only exist after I calculated the number of molecules contained in one mole of it.

image source:jmcadam

After spending years applying Avagadro’s number to everything I’m confident I can use it to determine the number of avocados in a green mesh bag; all I’d need to do is to multiply the atomic mass of an avocado by 6.022140857 × 1023 to get the weight of an avocado in grams. And if I found the weight of a green mesh bag of avocados in grams, and divided it by the weight of an avocado (from the above calculation), then I’d get the number of avocados in the bag; which would equal Avocados Constant.

Seems like I’ ready to test the Avocado’s Constant hypothesis. If you would excuse me. I need to go and rummage around in the basement in the hope of finding an old spring balance; then I’ll be able to go down to the local supermarket and start weighing the green mesh bags of avocados. When I’ve finished with Avocado’s Constant I think I’ll work on Garlic’s Constant.


Avogadro’s law

The Crazy, International, and Delicious History of Avocado Toast

What is Heisenberg’s Uncertainty Principle?