This week received from Mr. John Verhagen (Engineering Office of the City of Rotterdam) this fantastic picture of a very early CPT penetrometer rig. This picture was taken somewhere between 1947 and 1951 not far from Rotterdam harbour.
It shows a CPT penetrometer pusher on a 3 wheeler trailer. The pusher is powered by a hand-cranked winch and the force is transferred by means of a steel cable. Ingenious!
The CPT trailer was pulled by a decommissioned ex-US Army Willys jeep. More pictures on the “History of Cone Penetration Testing” page. Thanks John!!