On the steps down from Monteverde Vecchio to the Viale Trastevere, an enterprising chemist has created an outdoor billboard. "The best stuff in Rome," it says. I cannot vouch for that, nor for the accuracy of the formulae.

Two ways to respond: webmentions and comments

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Webmentions allow conversations across the web, based on a web standard. They are a powerful building block for the decentralized social web.

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