The new type of hydrogen target, which was to be used in the CERN/Serpukhov experiment, photographed in the actual experimental conditions during tests at CERN in February 1970. Inside the vacuum tank (the horizontal cylinder in the foreground) a small black horizontal cylinder filled with liquid hydrogen forming the target proper may be seen through the Mylar window. The liquefier is visible at the top left of the photograph, standing on a concrete block.