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lead and tallow. When the lead struck the bottom, small particles of the composition of the seabed would adhere to this sticky mixture which would then be identified by the leadsman and shouted up to the bridge along with the depth. This information would then be checked with any that there may be on the chart, and could assist in verifying the ship's position. It was a system that was used on the ships I was on when working the Indian coast and entering bays that were not particularly well charted. The senior apprentice had the responsible job of taking soundings which was done from a small platform, called the 'chains', that folded out from the rails at the break of the fo'c'sle so that the cast line did not go under the bow. There was quite a skill in casting the lead line as, because the ship was making way, it had to hit the bottom some way ahead of the leadsman, so that by the time the 'chains' platform was vertically above where the lead was on the bottom, an accurate depth could be measured on the line. To achieve this, the lead had to be swung in a vertical circle, over the head of the leadsman, and let go at the right moment to achieve maximum forward velocity. On one occasion, the senior apprentice, a short lad from Jersey, was having a job in getting enough swing in the line to get it to go round in a circle. He at last managed to get the lead moving fast enough to start the circle, but it ran out of steam just at the critical moment of 90 degree elevation, stalled, and came hurtling earthwards at maximum velocity nearly taking our good lad to the bottom. A fast falling 28lb lead is something to keep well clear of! It's interesting to note that the markings on merchant ship lead lines were very similar to those being used on the Mississippi steamboats: two fathoms was indicated by a piece of leather with two tails, three fathoms by three pieces of leather and seven fathoms by a piece of red rag (bunting) that was woven into the line, and many more. Each lead line was marked off in what were called 'marks' or 'deeps'. Marks were those depths at 2, 3, 5, 7, 10, 13, 15, 17 and 20 fathoms, and had a regulated system of marks. 'Deeps' were those depths in between the 'marks' and were sometimes indicated with short strips of marline or yellow bunting. If the depth was 5½ fathoms, the leadsman would call out 'by the mark 5, and a half 5', or sometimes just 'and a half 5'. And a depth of 6¼ fathoms by 'by the deep 6, and a quarter 6', or just 'a quarter 6'. With no handy VHF sets, the leadsman had to have a good voice to reach the bridge on a windy day! If coming in to anchor, or with the vessel stopped, the leadsman used to leave the lead on the bottom with the line tight so that he could advise the captain when the vessel had started moving astern. One ship I was on had a 'high tech' sounding machine that consisted of a small hand winch with about 300 fathoms of wire on its drum. With a lead attached the line could be let out fairly fast, and when the lead landed on the sea-bed the depth could be read from a dial. But even fancier was finding the depth through pressure: instead of attaching a lead to the line, an open ended glass tube with a sinker was attached instead. The open end of the tube was pointing down, and its inside was coated with chromate of silver which would turn into chromide of silver by any sea water that entered the tube due to the pressure at whatever depth it reached. Upon raising the tube the chromide of silver would then be measured against a scale that would indicate the depth reached by the tube. Those were the days when we operated mostly by using the KISS Principle (Keep It Stupidly Simple, as one dyslectic student put it to me), and we could fix most things that went wrong. But I have to admit that its great to flick a switch that activates a sound that travels at nearly 1500m/sec through the water, and watch a coloured screen show me, not only the contours of the sea bed, but also the type of fish that are down there. So long as I know where the fuse is and have a lead line handy, just in case, I'm happy! September/October 2012 Professional Skipper 17 VIP.S86