Huge thanks for all the votes, comments (and even some alternative designs by email!) on the short list for book covers. If you haven’t voted yet, please do so – will discuss the results with the publishers later this week.
Early zeppelins were made from beaten & stretched cow intestine. 250,000 cows were needed per airship. Germany 
and its allies had to abandon sausage production in the World War 1 cause. Blimey.
The world’s top 23 languages (by number of mother tongue speakers) [h/t Richard Cunliffe]
Some great genuinely tricky issues and nuanced discussions this week:
Randomized Control Trials: gold standard or dead end? Ricardo Hausmann attacks, Chris Blattman goes for middle ground.
Do children have the right to decent work (the working children’s movement) or is child labour basically evil and should be abolished (ILO)
Development as coercion. Thoughtful piece from Chris Blattman on developmental impacts of force v freedom & research from Philippines
And another from Chris. Six brain-stretching questions on political economy – wish I was one of his students
A smart new website factchecks claims on global health and development. Beward the ‘pants 
on fire’ gif!
Good choices in the 2016 Gates letter: Bill focusses on energy, Melinda on time poverty. Reviews?
Douglas Adams nails it on relationship between your age and your attitude to new tech. [h/t Chris Dillow]
Correction of the Day [h/t Steve Silberman]
