Original 1939 Folder Marconi Echo (1 results)

Soft cover. Condition: Very Good. T.S.S. Mauretania Echo Sounder Records. 16000 Metres. Magnetostriction Equipment. High Power. Thro' 2 - 21/2" Steel. N. P. Hinton. 26th June 39. Echotechnical Section. Original Marconi folder of echo sounder records created during the sea trials and maiden voyage of the RMS Mauretania. Light brown leather effect cardboard hole-punch type folder with 'Marconi' logo embossed to front. The folder contains about 45 echo sounder records which consist of thick brown paper sheets measuring roughly 19cm high and 30cm to 100cm in length (with a couple of shorter 14cm long examples). Each sheet has faint markings along it's length and 'T.S.S. MAURETANIA' handwritten along the bottom edge. Most sheets also have other information written on them. There are also a few diagrams and at least one sheet has a rectangular Marconi stamp to the rear. The Marconi Marine Company equipped the Mauretania with one of the most comprehensive wireless installations ever installed on a ship. The sounding device was fitted in the bridge and was used to indicate the depth of water under the keel. Echo sounders work by transmitting a pulse of sound downward to the sea bed and recording the time interval between emission and return of a pulse; the resulting time of flight, along with knowledge of the speed of sound in water, allows determining the distance between sonar and target. A paper recording instrument was used to set out the echo characteristics over time on a moving sheet. (please gallery for images of this type of instrument.) Every shipyard after constructing and launching a vessel performs a set of tests to ensure that all systems of the vessel meet the corresponding requirements assigned by the owner and at the same time conform to the rules and regulations of the approving classification society. This series of tests are clubbed under the heading Sea trials which are carried out at the sea after final outfitting and launching of the vessel just before delivery. I don't know much about N.P. [Norman Pullen] Hinton except that as well as working for Marconi, he was at one time or another a member of the Sub-Committee on Directional Wireless of the Radio Research Board, a wireless engineer for the Post Office, chief wireless engineer for Messrs Metrovick Supplies, Ltd., connected to Associated Electrical Industries Limited and was the inventor of the 'Hinton receiver'. Collation: White 'cover sheet': T.S.S. MAURETANIA MAIDEN VOYAGE . LIVERPOOL TO QUEENSTOWN. 17th JUNE 1939. Cover sheet is followed by 20 sheets of various sizes, some folded, each with 'T.S.S. MAURETANIA LIVERPOOL - QUEENSTOWN MAIDEN VOYAGE' handwritten along the bottom edge along with other information. Second 'cover sheet': 'SEA TRIALS 31st MAY - 3rd JUNE 1939 RECORDS FROM COFFERDAM PROJECTORS. DEEP SEA. - HIGH POWER EQUIPMENT. PLATE THICKNESS 2" - 21/2". Cover sheet followed by 14 sheets with 'T.S.S. MARETANIA' handwritten along the bottom edge along with other information. Third 'cover sheet': T.S.S. MAURETANIA. SEA TRIALS. 31st MAY - 3rd JUNE 1939 RECORDS FROM FORE-PEAK PROJECTORS. ON SLOPE OF 1 in 5. FIRING FORWARDS NOTE TWO ECHOES. [With small diagram of front of bow showing echo signals] Followed by 11 sheets (2 small) with 'T.S.S. MARETANIA' handwritten along the bottom edge alongside other information. Other information hand-written on records includes: 'Fore-Peak Projectors through 2 1/2"', 'Cofferdam projectors.', 'Re-echoes.', 'No transmission due to distance.', 'Note: improvement of sea bottom reflecting properties.', 'Showing tendency to sound forwards.', '0-50 fathom range. 50-100 F. Range.', 'Cofferdam Fore Peak comparison.', 'Note the forward spread.', 'Doubles close for shallows.', 'Opened out for deeps.', Note: Effect of sounding forward due to bows.'. Folder measures roughly 14.5 x 9.5 inches (roughly 23 x 36 cm). Weighs 616 grams.Some wear and discolouration to covers with verdigris type corrosion to metal 'fasteners' effecting first cover sheet.…