Aguttes

Three important scientific auctions this week: a 13-m (43-ft) Diplodocus skeleton (US$1.5 to $1.8 million), a first edition Luca Pacioli’s "Summa de Arithmetica" ($1.0 to $1.5 million) and a presentation copy of Charles Darwin’s "On the Origin of Species" ($200,000 to $300,000).

At 8.7 meters (28.5 ft) long and 2.6 meters (8.5 ft) high, and with a price tag somewhere north of US$1.5 million, this 155 million-year-old skeleton is not for everyone, but it is certainly one of the most impressive and imposing artifacts of natural history ever to go to auction.