These are some videos found on YouTube of Cheng Man-Ching demonstating his 37 posture form, sword form and also some push hands techniques. Videos will continue to be added as they are encountered.
The following video, without sound, shows Cheng Man Ch'ing as a younger man doing the form. Notice that the postures are more defined then in videos of him as an older man
As he aged, Cheng Man-Ch'ing's forms became softer and more graceful although the postures themselves appear less defined. He is incredibly relaxed in these older videos.