Movie 1. A red-dyed volume of glycerine runs down a smooth Perspex plane at 8˚ to the horizontal. For fun, a map of the UK has been placed under the Perspex, and some model buildings located at Cambridge, Oxford, Bristol and London. The current, initially uniform across the slope, at first spreads independently of the cross-stream direction (except near the sides) in accordance with (2.7). After some time the flow front becomes unstable with a wavelength given by (2.8).

Movie 1. A red-dyed volume of glycerine runs down a smooth Perspex plane at 8˚ to the horizontal. For fun, a map of the UK has been placed under the Perspex, and some model buildings located at Cambridge, Oxford, Bristol and London. The current, initially uniform across the slope, at first spreads independently of the cross-stream direction (except near the sides) in accordance with (2.7). After some time the flow front becomes unstable with a wavelength given by (2.8).

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. a) A heavy compositional current with a density excess of 0.1g cm-3 due to dissolved salt.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. a) A heavy compositional current with a density excess of 0.1g cm-3 due to dissolved salt.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. b) A light compositional current with a negative density deficit of 0.1g cm-3.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. b) A light compositional current with a negative density deficit of 0.1g cm-3.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. c) A heavy particle-laden current with an initial density excess of 0.1g cm-3 due to 23 micron silicon carbide grinding powder.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. c) A heavy particle-laden current with an initial density excess of 0.1g cm-3 due to 23 micron silicon carbide grinding powder.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. d) A particle-laden current with sufficient interstitial alcohol to make the initial bulk density less than the ambient.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. d) A particle-laden current with sufficient interstitial alcohol to make the initial bulk density less than the ambient.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. e) A particle-laden current with interstitial alcohol with the bulk density initially in excess of the ambient.

Movie 2. High Reynolds number gravity currents released into water in a channel 15cm wide, 8cm high and 100cm long, from behind a lock of length 5cm. In sequences a) to e), the lower view is an elevation and the upper view is a plan as seen in a mirror above the tank at 45˚ to the horizontal. e) A particle-laden current with interstitial alcohol with the bulk density initially in excess of the ambient.

Movie 3. High Reynolds number gravity current released into a linearly stratified fluid in a channel 26cm wide, 20cm high and 250cm long, from behind a lock of length 20cm. The blue-dyed saline current has a density of 1.10 g cm-3, and the ambient density varies linearly from 1.10 g cm-3 at the base to 1.00 g cm-3 at the free surface. The ambient fluid has three green-dyed marker horizons to visualize the internal wave propagation.

Movie 3. High Reynolds number gravity current released into a linearly stratified fluid in a channel 26cm wide, 20cm high and 250cm long, from behind a lock of length 20cm. The blue-dyed saline current has a density of 1.10 g cm-3, and the ambient density varies linearly from 1.10 g cm-3 at the base to 1.00 g cm-3 at the free surface. The ambient fluid has three green-dyed marker horizons to visualize the internal wave propagation.