Irving Harper, a pioneer of mid-20th-century design, died on August 4, 2015, at the age of 99. Harper worked for George Nelson & Associates on designs for Herman Miller Furniture Company from 1947 until 1963. His creations include the iconic Marshmallow Sofa (as well as the company’s red M logo), and the Ball Clock and the Sunburst Clock for the Howard Miller Clock Company. But industrial designers were rarely given public credit, and George Nelson is listed as the designer.

Harper was inspired in 1956 by some molded 12-inch diameter plastic discs that he upholstered and put together on a long metal frame. The strange-looking sofa was advertised as being more comfortable than it looked. (I sat on one and was very uncomfortable because I felt the spaces between the discs.) About 150 were sold by 1961 for $452 each, about $4,000 in today’s money. The sofa is still made by the Herman Miller company. Price —  $5,499. A rare original 104-inch marshmallow sofa auctioned for over $112,000 in May 2015.