Feedback: How many ducks in a row?


NEW technology may require, or at least inspire, new units. Thus Samuel Merchant proposes that "the 'duck' now seems to be the unit of choice for 3D printing costs". He sends a selfie taken at last year's exhibition "The Future is Here" at London's Design Museum, next to a graph showing that 3D printing of plastic bath ducks was cheaper than injection-moulding for runs of 400 ducks or fewer. By coincidence, Samuel was wearing a duck T-shirt.


Feedback looks forward to seeing a 3D printer large enough to churn out blue whales – and baths big enough to float them.


On a recent trip to Malawi, Malcolm White was startled to find a stiff paper bag in a hotel bathroom labelled with the request to insert one's "Sanity Towel" for disposal


TALKING of units, a steady stream of readers have developed the concept of the elephant as unit. Bearing ...


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