A view of part of the spark-chamber installation for the second phase of the CERN neutrino experiment taken during setting up of the equipment early in 1964. In the centre of the picture (no. 145), the vertical spark-chamber modules can be identified by the white lines along the edges of the mirrors that enabled one camera to 'see' along ail the gaps. Between the chambers are the magnetized iron plates that caused positive and negative particles to be deviated in opposite directions. On the right, the close-packed spark-chambers of the production region can be seen.