The Porthole Range of Brass clocks and barometers is made of solid, unlacquered brass with an opening bezel and bevelled glass. Tide clocks feature an additional hand which records lunar time over a 24 hours 50 minute period and so indicates successive high and low tides.
Explanation of the use of the tide clock:
The tide indicator hand should be set to high tide when the next high tide in your location occurs. The exact time of the next high tide can be obtained from official tide tables. As a general rule the best time for setting the tide hand is at high tide during a new or full moon. If it cannot be set during a new or full moon then we recommend checking it at that time during the next cycle. The tide clock is not a perfect predictor of high and low tides during a moon phase however at the same location and at the same moon phase it is surprisingly accurate.
Three sizes available
Small - 80mm Face and Dial - Back Flange 145mm
Medium - 115mm Face and Dial - Back Flange 186mm
Large - 143mm Face and Dial - Back Flange 220mm