Today’s photo is literally that, taken today while walking another section of the Humber bank, after far too long a delay in this project. More on this walk next time.
Back in 1939 the Humber Conservancy Board had at least four small ships/boats, two of which were still steam powered. The buoy ‘yacht’ was the largest of the four and was steam powered having been built at Earle’s shipyard in 1892. She was fitted with the necessary derricks, winches and tackle to use when lifting and moving buoys, this being her main purpose. This ‘buoy-yacht’ had a large crew of about 10, two of which were firemen.
The other steam-powered launch was built for ‘hydrographical surveying’. This was the process which determined most of the decisions related to the aids to navigation. The ‘echo sounding’ devise fitted on board was used to determine the configuration of the bed of the Humber Estuary, the survey vessel generally criss-crossing the Estuary from side to side, each survey sheet then put alongside the last to produce a three-dimensional plan of the Estuary bed. The ship had a transmitter on board and a receiver and soundings could be recorded at the rate of four per second up to a depth of 20 fathoms. It seems that even as late as 1939 this was considered a revolutionary process, for preceding centuries water depth had been determined by a man with a plumbline, the rope knotted in fathoms.
The other two boats described in the book (s.p.b.s) were powered by ‘petrol paraffin engines, one, wooden built of larch and teak, had a chartroom where maps of the Estuary bed were compiled. This boat was about to be installed with even better echo sounding equipment.
It is still today a regular sight to see the boat that maps the Estuary floor zigzagging back and forth across the Estuary.
(to be continued)