Hydro-Clockworks

Unlike the heated water used in England and the rest of Europe, Tang water clockworks don't pose any risk of scalding when in use. Our clockworks are mold-proof and won't wear down in a lifetime.

— Salesman's pitch for a water-powered music box, 1841.

This article discusses water-powered clockworks, mainly found in China or the Tangguo.

Utility

The crew stared when the heavily lacquered lady turned back to get another drink and handed it to them. Then, the carpenter poked the sailing master and whispered, "Did you see that water circuit? That lady isn't alive at all."

— Eyewitness account of an automated serving girl.

Besides keeping time, people used hydro-clockworks for entertainment, especially on long voyages. Talking drink dispensers, music boxes, and puppet theaters were some of the uses hydro-clockworks were put to.
From a practical standpoint, farming communities with Tangguo influence used hydro-clockworks to thresh grain, pound raw ingredients for cooking, and so on. The most obvious example is the presence of watermills in seafaring communities.
There were attempts to use watermills as a sort of cold engine for ships to avoid the problem of coal engines exploding. However, they did not catch on because watermills were bulky and took up more cargo space than coal engines.
Despite the failure of attaching hydro-clockworks to transportation, the general concept of using water for automated controlled temperature was inspired from it. The following summer cruises were made more pleasant by the use of water-powered fans blowing into passenger cabins.

Access & Availability

Common sight in the Tangguo.
Occasional curiosity in other nations.

Complexity

Presumably, water piping control is needed to turn on and off the hydro-machines.
Water-proofing is also a must as without treatment, metal and wood will spoil under excessive exposure to water.

Discovery

While the concept of clockworks was discovered in the pre-Christian era, further developments took place during the Tang, Song, and Ming dynasties from 618-907, 907-1279, and 1368-1644 respectively.