An Alarm Water-Clock, a Mast Hoist, and Window Designs
A device to wake a sleeper by water and counterweights, with a windlass and cellar windows
The most developed device on the sheet is an alarm "clock for the miserly spenders of time": water drips into a receiver until, balanced against a counterweight, it tips and jerks up the sleeper's feet to wake him. Leonardo also draws a windlass-and-frame for raising a mast easily, a starburst figure he labels "40 long lances born from one centre," and a trussed wooden covering shown in section. At the foot, three window sections lettered a, b, c compare the light, warmth, and view given by different cellar windows.
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Alarm clock that wakes a sleeper with water
Leonardo calls it a clock for the miserly spenders of time. Water from a hopper fills a receiver until it equals the water in the opposite scale-pan; the rising pan then pours its water into the first receiver, which doubles in weight and violently lifts the sleeper's feet so that he wakes and goes about his business.
Windlass to raise a mast easily
A device combining a windlass with a supporting frame, intended for raising a mast or spar (antenna) with ease.
Forty long lances radiating from one centre
A double figure of small circles from which rays issue, annotated as forty long lances born from a single centre. It reads as a design for a radiating array of spears springing from one point.
A way of waking oneself at will
A wooden covering shown in vertical section, connected to the waking mechanism. Its caption calls it a way of rousing oneself at one's chosen time.
Three cellar-window designs (a, b, c)
Three window sections compare the light they admit to a cellar. Window a is judged the most useless and coldest, window b the most useful, brightest and warmest with the widest view of sky, and window c of middling usefulness.
