Nadal

Rafael Nadal looks like Tom Cruise with his face smushed against a window.

Think Twice

There are a number of great maths channels on YouTube, such as Numberphile and Mathologer - but the most beautiful and elegant is Think Twice, where smart and smooth animation visualises otherwise complex formulae or theorems. For example, here's the derivation and properties of the Dragon Curve.

(Mr Puzzle has a nice review of some laser-cut puzzles including a Dragon Curve one here.)

Ancient Beech in Ill-considered Leggings

A return to a tree in Danes' Wood I'd only seen out of leaf, and which was hard to find with the wood in its summerwear. Turns out it's a beech and I can't tell my arse from my arbour.

Surprisingly tricky, requiring quite a lot of repositioning in order to get a good enough line for several of the re-pitches, but each stage was quite short.

The tree branches considerably all the way up, so there are a lot of choices to make, but once at the top you can move from place to place relatively easily with a long lanyard to play with. Also - great for limbwalking.

Inevitably I'd climbed about one metre higher than my rope would allow for a return to ground, and because of being too lazy to climb up and move my anchor point, I ended up using my lanyard to unclip from my zig-zag and drop to earth with my foot ascender still attached. Getting cramp in your supporting leg while trying to detach from a foot-ascender is both hilarious and agonising in equal measure.

BETTER Dancing in Movies

There's a video doing the rounds this week called Dancing in Movies, and it's proving to be impossible to avoid. 1.5 million plays on Vimeo. Virality huh... But it's no good. The tracks he chose are agonisingly undanceable and it doesn't match satisfyingly with any of the actual dancing, much of which is amorphous. It's just random clips of dancing with a weak musical backing.

This one, on the other hand, from three years ago, is an absolute classic. Every clip is achingly skillful, the track (Uptown Funk) is the most leg-twitchingly danceable track ever produced, and the dancing actually fits the rhythm of the song, which you'd think would be fundamental to a project of this type.