Describe work crews' first attempts at cooling off the lava flows of Heimaey in 1973.

At first, work crews use fire hoses in an attempt to cool down the 1973 lava flows on Heimaey moving towards the town and harbor. The result is a chilled wall of lava. The lava cools down somewhat, but the flow does not stop. Additional pumps are then brought in to increase the volume of seawater poured onto the lava.