face water turbidity in the entrance to Chesa-

A comparison of vertical drift-envelopes to conventional drift-bottleP3 Abstruct-A comparison of the recovery sites of vertical drift-envelopes and of bal-lasted drift-bottles released simultaneously at common locations in Nantucket Sound off Cape Cod substantiates a preliminary con-clusion, based on small tank experiments and simple calculations, that vertical envelopes move more rapidly through the water due to direct wind influence than do ballasted bot-tles. The bottles therefore provide a truer indication of surface currents than do the envelopes. Many types of surface floats have been advocated for use as lagrangian indicators of surface currents. Setting aside the doz-ens of drogue system designs (Monahan and Monahan 1973b) where the drogue-buoy’s position is monitored frequently dur-ing the drift, and considering only those small surface drifters that are released in clusters, one still has at least a dozen dis-tinct designs to choose among (Monahan and Monahan 1973a). Two of the currently most popular surface drifter designs are the ballasted drift-bottle and the vertical drift-envelope. The drift-bottle has been in use as a surface current marker since 1763 ( Carruthers 1956; Gakkel ’ and Samsoniya 1961)) while the vertical drift-envelope has been introduced since the close of the Sec