In the previous article we have introduced the simplest hydraulic timing device - jug water bell, which is the simplest in the corresponding other water clock or timing device; in the next and subsequent articles, The author will give you a little introduction to one of many talented scientists and inventors in the Arab world during the Abbasids (750 - 1258 AD): Al Ghazali Most of the timepieces of the hydraulic chronograph and candle chronograph of the classic inventions of that era were recorded in the book "Manufacturing Knowledge of Sophisticated Machines", booked in 1250. In the previous articles, the background of these chronograph devices was mentioned. For the time being, the Abbasid dynasty is referred to as the "great meal of black food" in the historical data of China. Moreover, during this period The Arab Empire, both economic power, military strength or land area, far surpassed its predecessors. Therefore, the territorial expansion and economic prosperity have brought tremendous wealth to the dynasty. At the same time, it is also ready for a leap in science and technology, and more because of the centenary translation movement from the 10th to the 11th centuries AD. The Arab Empire and the Abbasid Empire received a large amount of manuscripts and cultural relics from West Asia, Europe, Greece and even Egypt. After a century-long centenary translation movement, the Abbasid cultural leadership started Cultural and economic reforms of their own accord and the emergence of a large number of cutting-edge inventors and their finished products, including Al Ghazali, beginning in the 12th and early thirteenth centuries. The Hydrodynamic Clock, appearing in this paper, has a relative proportion of full clocks and is also a relatively mature astronomical clock with a large number of mechanical linkage and timing mechanisms. There are only one hydraulic chronograph with an astronomical demonstration in the book, and one with a similar chronograph. And this is far more complicated than the "jug bell" and has a different dynamic structure than the "elephant water bell" mentioned in the first article. In this hydro-astronomy, the same principle of gravity and buoyancy is used to make the bell work. When it is set up, it is a one-sided wall or wall, with a row of musicians at the front of the wall, Hand (flutist) with one hand on each side of the tambourine, one double drummer and two cymbals in the middle, each playing at 6 o'clock in the morning to indicate the time of 6 o'clock, and at 6 o'clock, the timing process Halfway through every three hours will play until 12 o'clock. Because of this unique timekeeping practice instead of playing every hour, scholars later found it to be demarcated at sunrise and beyond, and some scholars think it may be related to Islamic Therefore, it is assumed that this clock may be a special timekeeping device for placing believers in the open space and reminding Muslims to attend their church on time, so this hydraulic astronomical clock will also be called a "call bell." There are two pillars on each side of the musician. There is a prominent table above the pillars. The table is an open-bellied bottle with a cup of copper and a channel in the bottle. , A recessed wall niche and a standing falcon in the niche. Each hour the Falcons on both sides of the body simultaneously explore the body of the niche and fall out of its mouth Two bronze balls fall into the bottle below the front of the niche, and the copper ball squeaks on the copper cup in the bottle. On the niche, there is a long row of long strips divided into 12 small windows, And there is an air hole above each small window, a new moon on the far left is used to indicate the time; at the very top of the water clock there is a big disc with the sun, the moon's trajectory and the ecliptic ten Nirvana's instructions for running; there is a semicircle in the middle of the musician, which is divided into 12 small circles, each of which is fitted with a piece of glass and the sun's position in the day is judged by looking at the brightness of the glass (Figure 1) . Figure 1 Hydrodynamic Astronomical Clock On the back of the bell, there is a tube tank on the right, almost as tall as the wall, which is divided into four sections during production and installed one by one during installation, the water in the tank supporting the entire water clock for a full day and night, The top has a copper hollow pontoon which floats in the water tank, the pontoons are connected with ropes, the ropes are connected to a big reel by pulleys, and the other wheel coaxial with this wheel is also wound with ropes, The timing indicator means and the striking mechanism are used for towing it, the ropes on the second wheel are connected to the trolley above the wheel, and the second wheel is half the area removed at the time of manufacture for connecting with the front 12 glasses The wafer corresponds to the day and night conditions; the front of the small tackle extends in the shape of a half moon for indicating the time on the front; it also has a stanchion on the tackle for timekeeping while indicating the time, and on the other side of the tackle A counterweight is used for balance. In the 12 above the top of the block are divided into two levels one on top: the upper is a two-door composition of the door frame above the door frame with a portrait of a wooden board, and the board is a small nail hanging On the top, it slides off the nail with a slight push; there is a rope attached to the top of the board. Here's an introduction: Above the 12 subdivisions just mentioned there is a special wooden tank made of a single piece of wood, which is engraved with 24 independent chutes, and each chute There is a hole in the front end, the chutes are arranged two by two, two groups, a total of 12 groups; each chute will have a copper ball, for the final fall from the falcon mouth time; and in each group of inclined A groove is provided at the front end of the groove, and the shafts of the stopper are mounted on the same side. After each stopper, a small rod protrudes from the end of the groove with each of the just-mentioned Portrait board connected to release the copper ball. Also, there is a juxtaposed upper end between the wooden slot for the copper ball and the lower twelve sections, and the lower middle slot is used to catch the copper ball released from above and there are two Falcon brass on both sides (Figure 2). The falcon is cast in bronze and made as light as possible, with a hole in the back of its head connected to the copper tube just before, and a tee in its mouth to allow it to lean forward and Falcon The feet also have mating weights that allow them to be pulled back after they have been tilted forward and spit out the copper ball (Figure 3). Back in the 12-zone structure: Each portrait is hung high and pushed down by the pole on the trolley, with a rope attached to the portrait plate to connect with the top flap to release the timed copper Ball; under each portrait card there is a door frame with two door panels, the door panel is closed, and under each door frame there is a small window with a flap on which the two sides are marked with different colors The moment represented. The flap is held in place by a small mechanism and turned down when it is time to change the color on the plate. And at the 6th, 9th and 12th hours, there is an additional counterweight attached to the portrait card to trigger the later authorities. Figure 2 hydraulic bell back view Figure 3 Falcons structure Now look down, at the bottom of the column water tank has a water valve, shape and structure similar to the contemporary faucet, and the water valve in front of a throttle, which is to control the water flow to adjust the operation of the entire water clock Speed, its structure will be described in detail below. Underneath the throttle valve there is a round, perforated tray with a shaft underneath the tray so that the entire tray can be pivoted about the axis. In addition, there is a conduit in front of the water tray, in front of the conduit, there is a double head to guide the water; and below the water pipe there is a water tank divided into three partitions, At the bottom there is a long, flat tank. The water from each tank flows into the lower tank. There is also a conduit on the edge of the tank to direct the water to the next tank. At the bottom of each of the three separated tanks there is a conical water plug, one for each water plug, and each one passes through a corresponding idler wheel connected to the previously mentioned hooks At 9 o'clock and 12 o'clock on the back of the portrait card hanging weight on the weight, and each wire through the fixed loop on the catheter, so that when the 6th when the breeding weights and portrait When the card falls, it tightens the thread and lifts the water plug in the water tank. At the same time, when the wire is tightened, the wire transfers the water pipe to the second tank and begins to store water in the second tank . Each tank will be filled with the same amount of water in three hours, and at 9 o'clock, the counterweight on the portrait card at the 9th hour falls at the same time as the portrait card, pulling on the wire, pulling on the water plug, The catheter is diverted to the last, separate tank; it is important to note here that in the last tank, the wire on its water plug is not connected to the catheter, but the wire is connected directly to the portraits at 12 Therefore, when the last weight is pushed down, the double-headed pipe does not rotate, but the water plug is directly pulled up and the water in the last water tank is put into Under the sink (Figure 4). Figure 4 Separated water tank and its control system When water flows out of the duct through the duct below, it flows to a wheel mounted on a long shaft and has a number of pins on the long shaft that also rotate as the water pushes the wheel , And its pin in the rotation will be struck in front of the stick out of the stick, when the link is struck when driven in front of the musician drums hit the drum and cymbals, in order to make audible time. There is also a sink beneath the waterwheel. When water flows down from the waterwheel, it will flow into the sink and into the airtight box along the conduit on the sink, with a conduit at the upper plate of the box A gas whistle was placed at the end of the catheter, placed beside the front trumpeter (flutist), and a U-shaped siphon was installed on the lower plate of the sealed box to drain all water when the water was full. Therefore, as water flows into the sealed tank from below the sink of the water wheel, the air is also forced into the upper duct and sounds when the air strikes the whistle. When the water passes over the siphon U-shaped bend, it will be completely drawn out of the sealed box. After the water is drawn from the sealed box, it will flow into the water tank under the sealed box for the next replacement (Figure 5). Figure 5 water wheel, musician and flutist movement structure In all timing, when the timing begins, the water in the column tank will fill up and begin to flow out quantitatively. As the water level in the tank drops, the copper hollow pontoon on the surface of the water begins to descend and pass over it The connected rope drives the first reel to rotate, while the other coaxial reel also rotates at the same time, and the rope on the wheel is pulled to pull the trolley placed thereon. When the trolley moves forward, On the connection of the half-moon-shaped indicator car also forward, the same car with the column also pushed the first portrait card in the first hour, portrait card falls, on the one hand will be below the door open and top On the other hand, when the portrait of the pull the top of the block, the flap open, the release of the wooden groove in the two copper ball, copper ball through the wooden groove and The pipe below it enters the falcon's head on either side and the Falcon's head changes its center of gravity so that the two falcons lean forward at the same time as the copper ball falls in its mouth into the bottle below it, In the bottle of copper é“™ on the sound, Here come the hour. In the five hours before the clock was clocked in such a way that the musician on the receptionist below would be added to the clock after 6 hours and beyond, Before 6 o'clock, the water tray in front of the throttle accumulates water into the first divided tank through the conduit and at 6 o'clock, the water in the first tank is nearly full, and at 6 o'clock, Will be released to promote the waterwheel in front of the musician to play music, and after 6:00 every three hours, that 9 o'clock, 12 o'clock moment, in addition to Falcon can be timed out, the musician will Falcon spit copper After the ball began to play music, the corresponding structure has been mentioned in the previous article. Figure 6 Astronomy indicator disk Here to mention a bell on the top of the astronomical, day, orbit orbit (Figure 6). At the very beginning of the study of such water bells, I would have assumed that the astrophysical system above was connected (or hoped) to the timing mechanism below; however, as I later included in the study of the astronomical indicator disk, I found The astronomical demonstration plate on this clock was actually made manually to operate it. In addition, its basic structure of the astronomical indicating plate was actually a circular wooden plank with sun and moon running tracks and zodiac motifs , With its axis connected to the rear and another disc marked with holes on it, and when day and night were completed, the person in charge of the water clock changed the position of the sun and the moon therein, and all the objects Homing, and putting the water back into the column tank, such operations with relative manual override and manual adjustment are of course not classified by the automatic clock classification for now, but in the 11th-13th century Arab Empire , And even the whole world, even in Europe, there are almost no contemporaneous devices of similar philosophy and operation. Therefore, it is placed on the historical background and the historical ring Habitat context, such a clock is already quite advanced and quite successful! Figure 7 Throttle valve In addition to introducing the basic daily operation of the clock and its structure, it is important to mention that the throttle control valve (Figure 7), which is the core control mechanism for full-scale operation set in front of the water outlet, The reason why the article puts forward is that this structure is very subtle to control the operation of the clock so that the clock can adjust its operation speed according to the change of the sun's sunrise and sunset within a year and precisely control the The sunrise and sunset times of the day make the sunrise and sunset times indicated on the bell coincide with the sunrise and sunset times of the sun century. For example: when the summer solstice (June 22) the sun's sunrise time is the earliest, the sunset time is the latest, so the longest time accounted for the day; the night accounted for the shortest time. After the summer solstice, the sunrise time is gradually pushed back, and the sunset time is gradually advanced, so the time in the daytime is shortened. The dark night occupies more time; until the winter solstice (December 22), the sunrise time is the latest and the sunset time is the earliest, so the day takes the shortest time and the night occupies the longest time; on the day of the equinox (3 January 21) and the autumn day (September 23), the sunrise and sunset times are equal and the time is equal between day and night, that is, day and night equally. To adjust the speed of the entire clock during day and night and sunrise and sunset: Al Ghazali added a throttling adjustment mechanism to his design, which makes the water discharged every day at a different rate, So as to control the running speed of the clock and make the indicated time correspond to the sunrise and sunset times of the day. To achieve the effect mentioned above, Al Ghazali used a movable throttle design. The throttle is made up of four basic parts, with a ring behind it, a rotatable disk in the ring, 12 large partitions on the disk, and 6 small partitions in each large partition , And in each small subdivision is also divided into five divisions, each subdivision are so divided, so a total of 360 small subdivisions in the plate, every day to manually rotate a cell in the center of a The root cannula leads straight to the front and has a copper outer tube on the tube, a ring in front of the outer tube, and a semicircular shell in front of the disk. When you turn the chassis, the amount of water will decrease accordingly, and after its accurate calibration, the water volume and water flow speed of each day will correspond to the sunrise and sunset times of the day, and finally, after finishing, Of the devices play a very important role in all the clocks, because this clock is no longer a mere clock, but a device that can adjust its operating speed and operating cycle, and according to the operation of the sun In operation, this sublimated this clock into the only chronometer that, by adjusting its speed, accomplished the astronomical clock of the cyclical nature of its cycles. Up to now, though, as compared with the earlier appearances of the Chinese Song Dynasty Hydrographic Observatory (AD 1088) and the late appearance of the large European mechanical bells and bell towers, clock tower (13th-15th century AD) The clock still needs to be watched by more than one person, and the entire chronograph needs to be reset in a relative period that is not yet resettable by mechanical operation, but placed in the context and era of the times In the context of the environment, the study of clocks or timepieces in all parts of the world has been relatively stagnating or even regressing, except for the Arab world. Looking at the place of civilization in the world as we mentioned earlier, In the Central Plains region of China, the meteorological observatory was almost destroyed and still in the midst of war with the northern ethnic regimes and the Mongols. They were completely unable to withdraw from the study of clocks and watches. In Western Europe, the dark and technological development of the Middle Ages In its slow period, from this point of view, such hydrometric astronomical clocks in the relatively developed Arab region have their own relative characteristics and ingenuity From this point of view, it is also understandable that it needs a lot of manpower for maintenance in operation because it is acceptable in the prevailing Arab culture at that manpower occupation in the operation of a hydraulic timing device Relatively more than the proportion of. Therefore, in the study of this clock, it is also understandable that the situation just mentioned can also be understood as a characteristic of the timekeeping device at that time. The above is an introduction to the overall structure and function of a hydraulic astronomical clock. In general, the structure of this clock has been quite sublimated and developed in comparison with the previous wide-mouth water clock. The basic principles are similar, but the timing and speed regulating mechanism of this clock is actually a technological innovation based on a wide-mouth water clock. Such water clocks, in contrast to elephant water clocks, sometimes introduce new driver structures for the exploration and development of new driving structures and bring the timing astronomy and accuracy to a new level. It is also the only chronograph with an astronomical demonstration in Al Ghazali's book Manufacturing Machinery for Compact Machines. Describe this article as much as possible and share it with fellow colleagues. This article is reproduced, does not represent the world position of million table.