# Seven things you didn’t notice in Issue 04

How many did you spot?

With just a few days to go until we launch issue 05, we thought it’d be fun to share a few bits and pieces that we hid around issue 04. If this gets you excited for issue 05, why not come to the launch party on Tuesday?!

## Scorpions

Since we published the horoscope in issue 03, scorpions have been running around all over Chalkdust HQ. Three of them managed to sneak into issue 04.

## Old Bear

To illustrate Proof by storytelling, we used a lovely drawing of a teddy bear learning to count.

But this is no average bear: this is Little Bear—and he is sitting on Bramwell Brown’s lap as Jolly Tall, Ruff and Rabbit look on. These are the toys from Old Bear. Jane Hissey, the author of the Old Bear books, very kindly allowed us to use this picture, plus the one on the contents page.

## Melbourne

In Problem solving 101, a traveller is rushing to catch a flight to Melbourne.

Stephen, who wrote the article, is from Melbourne and may or may not have had to run for a flight.

## A hidden number

In the biography of Hedy Lamarr, the diagram to the right was used to illustrate frequency hopping. The code sequence binary number (in green) is 10100111001. If you convert this to base 10, you will get 1337.

I put this one in to entertain myself (and probably only myself): in the same diagram, the colours are the same as the colours used in my text-based adventure game Adventure! Villainy! Excitement!.

## Number -3

We put a particularly stupid joke into Top Ten, which is worth a mention here:

## The crossnumber

The header of the crossnumber page contains a pattern of black and white squares:

Eagle-eyed readers (or those who spent a long time staring at crossnumber #3) may have noticed that this pattern was taken from crossnumber #3:

How many hidden jokes can you find on Tuesday, when issue 05 will be launched?

Matthew Scroggs is a postdoctoral researcher in the Department of Engineering at the University of Cambridge working on finite and boundary element methods. His website, mscroggs.co.uk, is full of maths.
@mscroggs    mscroggs.co.uk    + More articles by Matthew

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