Today being Sunday was the day for an early rising and then a trip down to the paper shop for our copy of the ‘Sunday Times‘ It was quite a nice bright and not particularly cold when I started walking down, accompanied by a bit of Bach on my ancient iPhone which is my Sunday morning treat. On such occasions, I often think of little numerical puzzles I have encountered – for example, I have discovered that with a bit of rounding a square metre is 1.2 square yards- conversely to convert square yards to square metres, one multiplies by 5/6. As a case in point our communual green area, minus the BioDisc is 300 square metres which it is easy to convert into 250 square metres. But it whilst I was doing a bit of internet searching into push mower rotation speeds that I came across the opinion that revolutions measured in revolutions per minute (rpm) is a particularly pointless idea and one to which we cannot really relate. For example, I know that at my 2mph my little push mower will rotate its blades to give the equivalent of 2200 rpm which is about three quarters (2900 rpm) of the conventional standard for hover mowers and some petrol driven mowers. Now 2200 rpm sounds not to be a particularly fast rate but if you convert it into seconds, it becomes 36.7 revs per second, which ‘sounds’ a lot faster. Again, to try and get my mind around the magnitudes of revolving objects, I now know that a human blink has a typical duration of one third of a second. Now my trusty little lawn mower will deliver a cut with one of its blades at the rate of 12 for each eye blink. Now rather than my ‘slow’ 2200 rpm, I have an incredibly fast 12 ‘cuts’ per blink-of-an-eye which sounds satisfing fast – but all of the statistics are essentially the same. On a similar theme, there is one fact that had stuck with me since my GCE ‘O’-level days and that is a little formula that ‘60 mph is 88 feet per second‘. With a bit of rounding up to 90 this is 90 feet (or thirty yards per second). I mention this only because in my late 20’s I was involved in a bizarre accident in the Polytechnic in which I then worked. The campus straddled and was criss-crossed by some busy roads. One of these was a ‘T’ junction and approaching one of these a driver ‘fainted’ and crossed the road, hitting me first and throwing me into the air and smashing both my legs and taking two of my students on its bonnet through some iron railings. I reckon the car was going at about 40mph and was about 10 yards (30 feet) away from me before the car accelerated across the ‘T’ junction and hit me. As 40mph is 60 feet per second, then I had about half a second to react to the car speeding towards me. Meg’s father, when we recounted the story of the accident to him could only observe ‘Why didn’t he jump out of the way?‘ All that I can say is that I had just about enough time for my brain to register to not continue walking forward and hence the car hit me with the corner of its bumper rather than full on (when I might have been killed outright) I just thought I would mention how some of these equivalences might work out in practice (As a sequel, the ‘fainted’ driver recovered and fled the next day to Florida where our lawyers served a High Court writ upon him and the case came to court some 5 years later.) Incidentally a ‘fainted’ body at the wheel of a car is not legally responsible for their actions and therefore a legal case where one has to prove that the driver was ‘at fault’ is difficult to construct – but that is another story which I will not go into just now).
Around Easter time, I always like to listen to a rendition of an oratorio, typically broadast upon Radio 3. Today, I looked at the offerings for Palm Sunday and was pleasantly surprised to discover that there was a live performance of J.S Bach’s ‘St John Passion‘ so Meg and I particularly enjoyed listening to this whilst we were having our Sunday lunch and a pleasant relaxing read of the Sunday newspapers. Later in the week there is a performance of ‘Matthew Passion‘ on Wednesday evening (rather an odd choice of day as one would associate this with Good Friday or Holy Saturday (Easter vigil). When we go to church next Saturday, there will be a special Easter service starting at 8.00pm (when it is just about getting dark) when a special ‘flame’ accompanied by candles. I learn from the web that by Constantine’s realm in the fourth century CE, the night of the vigil of Easter began Saturday at dusk, with the lighting of the ‘new fire’, including a large number of lamps and candles and the paschal candle. The paschal candle is very large, made of beeswax and fixed in a great candlestick created for that purpose; it is still a significant part of Holy Saturday services.