An account of the speaking trumpet, as it hath been contrived and published by Sir Sam. Moreland Knight and Baronet; together with its uses both at Sea and Land. Printed at London an. 1671

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Abstract
The Author of this Instrument relateth first the several Tryals made with it; of which the most considerable was, that the biggest of those that have been as yet employ'd, turn'd Trumpet-wise, being 5 foot 6 inches long, and of 21 inches diameter at the great end, and 2 inches at the little; When by his Majesties special command it was tryed more than once at Deal Castle by the Governour thereof, the voice was plainly heard off at Sea, as far as the Kings Ship’ usually Ride, which is within two and three miles, at a time, when the wind blew from the shore.

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