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The dynamics of a polymer network are studied by direct view observation of the motion of a single point within a single polymer. Taking advantage of rather rigid biological microtubules as a case study, we expand the space and time scales of the system to those accessible by optical microscopy and standard video tools. Tracking is achieved by chemically attaching an optically resolved microsphere to a single point on the filament. We study the time dynamics of this point, without spatial averaging inherent in scattering methods. It is shown that the mean square displacement of the individual point is sensitive to local filament and network properties.