Last month the temperature in the UK rose above 40 degrees Celsius for the first time. Depending on where you live in the world this may not seem very high. But for many of us it caused a great deal of concern. We were worried about vulnerable people and there were news bulletins about how to care for our pets. We were pretty much advised to stay at home.

As both my husband and I work from home we have a lot of flexibility. We went to the island of Anglesey, Wales, in our little caravan where it was at least ten degrees cooler. The caravan was surprisingly cool inside. We kept the shades down on the side that the sun was shining on and opened all the windows. The sea breeze passed through and we were amazingly comfortable. We also sat on the beach too and me and my dog paddled in the sea to keep her cool. She even had her own sunshade. These high temperatures are of great concern as they illustrate the impact global warming is having on our planet.

On cooler days we got out and explored the island. We took a boat trip and saw puffins, seals and even a porpoise. The island used to be a key source of copper and we looked at the remains of the quarries and some of the exhibits at Aldwych. Holyhead played a significant role in the postal service between London and Dublin and we learnt about the history of this. My favourite day was visiting LLanddwyn Island – this is described as the most beautiful place in Wales. It was indeed beautiful, although I think much of Wales is beautiful.

The next part of this blog post is to use the number 40 to take me somewhere in the world that I did not know in advance. I discovered that Virgin Atlantic flight VS40 flies to Chicago from London. Thus, Chicago will be my destination.


Chicago North Beach – c/o

What do I know about Chicago? I have been through Chicago’s International Airport (O’Hare) at least twice but didn’t stop to see the city. I do remember seeing Lake Michigan from my seat within the plane and thinking how impressive it is.

To my great pleasure I have discovered that Chicago is a super city for cycling, considered one of the best in the United States. I would particularly like to ride beside Lake Michigan. The circumference is well over 1,000 miles but it is possible to do a pleasant North Shore ride taking 3 – 4 hours as described here. There are suggested routes all over the city as described here.

Food opportunities had been a huge plus when visiting anywhere. Sadly, for medical reasons, I am currently on a gluten-free diet. I also must avoid salt and too much fried / oily food due to kidney disease. In short the usual joy of eating has been a bit squashed. I look at a menu these days and often feel rather sad. However, the diet is keeping me healthy and I feel much better so I can’t complain. And I can still drink alcohol and eat fresh fruit and vegetables, meat, rice, chips (yay) and things like soup. Japanese food is ideal – sushi is wonderful. So all is not lost.

So rather than food I will concentrate on what I could do in Chicago apart from cycling. There are some suggestions here. I love taking cruises, even though I’ve never been on an overnight cruise, and would seek out all the day cruises I could. There are an enormous number and I would love to learn about Chicago’s history and architecture from the comfort of a boat. I love art too and would definitely visit the art museum.

By coincidence Chicago is the backdrop of part of a novel I’m reading at the moment – it’s the latest one from Lisa Jewell – The Family Remains. I feel much more connected with Chicago as a result. I’ll write a review of this in August’s newsletter.

Before reading up about Chicago I wouldn’t have been particularly interested in visiting. We spent a month in the US in 2019 and could have gone there. The cycling sounds wonderful and I would say that if I happened to travel into O’Hare I would definitely stop off if I could – a 10/10 – and that it would be high on my list – say 9/10 – if I was visiting my family who live in St Louis.

Real World and Theoretical Properties of the Number Forty

For this blog post I’ll share two interesting properties of the number forty which aren’t related to number theory and one which is.

Firstly, forty is the only number in English which, when spelt out in full, has its letters in alphabetical order.

Secondly, -40 degrees is the only temperature that is the same in both Fahrenheit and Celsius.

And 40 has a property that we’ve seen before: it is a harshad number (or Niven number). A harshad number in base 10 is divisible by the sum of its digits.

To demonstrate that 40 is a harshad number:

4 + 0 =4

40/4 = 10

It would appear that this property isn’t very common. So finding and testing for Harshad Numbers is a minor challenge people have found interesting. However, as with many aspects of number theory, there don’t appear to be real world applications.

Final Thoughts

One of the most wonderful things about writing these blog posts is discovering new places to travel to. I would never have considered Chicago as a destination before and now I am itching to go.