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(16th Century B.C. or earlier, Egypt) The ancient Egyptians were one of the first cultures to widely divide days into generally agreed-upon equal parts, using early timekeeping devices such as Sundials, Shadow Clocks, Merkhets & Plumb Lines used by astronomers of the period. In times when people's activities were limited to daylight, shadow-casting instruments called gnomons were used to distinguish broad divisions in the daytime. Gnomons were eventually combined with scales to produce sundials, which allowed people to tell time by measuring the length or direction of the shadow cast by the Sun. An Egyptian Sundial from about 1500 B.C. provides the earliest evidence of the division of the day into equal parts. Marks on the dial link the length of the gnomon's shadow to a standardised unit. The ancient Egyptians made the first Sundials. Before the division of the day-night period into 24 equal hours, the number of hours counted during any period of daylight was held constant across the seasons; thus, an hour in summer lasted longer than an hour in winter because the daylight period itself was longer. Sundials had to be specially made for different latitudes because the Sun's altitude in the sky decreases at higher latitudes, producing longer shadows than at lower latitudes. Not everyone in the ancient world realised this. Interestingly, a Sundial brought to Rome (41°54' N) from Catania, Sicily (37°30' N), in 263 B.C. told Romans the incorrect time for almost a century.  
Muslim astronomers care about manufacturing this astronomical device, The Astrolabe, which they inherited from the Greek civilization, they also developed it, and wrote great valuable books on how to use it. The usage of this remarkable device, astrolabe, continued until the nineteenth century and it is not known specifically who invented it, some referred to the Greek Scientist Hipparchus (BC) as mentioned in Ptolemy's book, Almagest (150 CE) Muslim scientist Mohammed ibn Ibrahim al-Fazari (died in 180 AH) is the first scientist to write a book in description, manufacture, and the use of the astrolabe, and he was the first who have made Astrolabe in Islam. Muslim scholars and scientists concerned about the Astrolabe and gave much attention to its huge role in determining the times of worship (Prayers), the direction of Mecca, and the solar and lunar eclipses, as well as its important role in astronomy and making Zij (Astronomical Almanac), determining distances, and to identify scientific measurements and most importantly the knowledge of the time at night by the stars and during the day by the sun , so The members of our astronomical society made a lot of astrolabes to understand it and to know how to use it.  
Shadow Clocks, another form of Sundials came into usage. The Shadow Clock divided night time into 50 parts, with an additional 2 twilight hours in the morning and evening. It was made up of a long stem divided into 6 parts, and an elevated crossbar that cast a shadow over the marks. This early clock was positioned eastward in the morning, while at noon it was rotated to face west, measuring as the sunset in the opposite direction. Ancient Egyptian Obelisks were larger, more public designs of Shadow Clocks; markers around the obelisk would indicate units of time, and indicated morning, afternoon, the summer solstice (the longest day of the year), and the winter solstice (the shortest day of the year).  
Quadrants mean a quarter of circle made on the wall or paper for use in observations and invented by the Muslims and the Quadrants were important instruments at the great observatories as in Maragha and Samarqand Observatory, where Ulgh Beg built in Samarkand observatory huge Quadrants( around three floors tall) and others Reference has been made for when Ptolemy Quadrant on the wall The small Quadrants made from metal or wood was invented by Muslims in the third hijri century and has several types of them as : Quadrant of almucanteres is a quarter of the astrolabe where the altitude lines are drawn called almucanteres. Sine Quadrant is a quarter depends on the Sine and cosine of the angles used in trigonometry, Professor Samir El-aidy member of Astronomical Society made a lot of quadrants.
This instrument referred to al-zarqalli the inventor, Zarqalla plate is one of the types of astrolabe, but it includes the all latitudes of countries where not limited to use on the latitude of a particular measurement. Abu Ishaq Ibrahim ibn Yahya al-Naqqash al-andalusi known as zarqalli where making very accurate astrolabe and he wrote a treatise on using and making Zaraqalla Plate composed of one hundred chapters supported on Muhammad Ibn Abbad It contains important making and the use of Zarqalla Plate. As well as Muslims , Zarqalla Plate used by Europeans at the beginning of the European renaissance has been used by Copernicus in some of the astronomical observations.
This is the Linear astrolabe was invented by Muslim Scholar Sharaf al-Din ibn Muhammad al-Tusi, who died in 606 AH and the manufacture of a stick of wood or ivory, and dropping a vertical line by a length and only this instrument depend on mathematics and Geometry in the projection in the concept of dimensions that were not present at the era, Henri Michel made one of ivory, as it appears in the picture.
Horizon Plate is a plate includes horizons of many astrolabes for many Latitudes (comprehensive plate), but it did not need to change plate at each latitude as in the case of standard astrolabes where the all horizons for many latitude presented on one plate instead of many plates , This is the beginning of the comprehensive Astrolabe ( Universal Astrolabe ) , made by Muslim scholar Ahmed bin Abdullah al-Baghdadi Marwazi al-hasib Habash, who died in 250 AH , He has written a book explaining the work and use of it.
Is the Plate made by the muslim scolar Khalaf bin al-shekaz al-andalusi and named after him and the idea is that light when drawn off from the point of the spring equinox and fall to the level of two points passes the winter solstice and summer and perpendicular to the equator and produces a plate gives a vertical section of the sky with the poles other regular astrolabes imagine made out of light from south pole and fall on the equator.
Zij is a table used for astronomical observations and astronomical calculations and Zij plates are instruments where the astronomical tables drawn on plates , the first one invented this instrument was Muslim scholar Abu Jaafar Al Khazen, who died in 355 AH and called it Zij al-Safa’h A he wrote a treatise entitled Zij al-Safa’h describing the instrument and how it work and then came the Astrolabist Hebat allah Bin Al-Hussein Bin Yousef Al-Baghdadi, known as al-Badi` al-Astrolabi died in 534 AH he made one of this instrument followed by Muslim scholars in the manufacture of these instrument as ibn al-Samh died in 426 AH, Ibn Zarqala died in 493 AH and Abu Salt died in 529 AH and others.  
Sophisticated instrument is made up of a circle with a small radius of 22,5 cm by illustrated of the Islamic world map from China to Andalusia, with a ruler Astrolabe map for ease of use and the magnetic compass in the midst of the map drawn and placed Mecca and the machine accurate in determining the distances to Mecca, the direction to the schemes were True identify trends only, without spaces, and on this instrument is one hundred and fifty Islamic cities ,this instrument discovered in 1989 which sold antique copy at auction in London and its history as the year in 1100 and sold in another version in 1995 late in the history of the industry slightly be the first map on this instrument prior to the map prepared by a historian of science Amani Carl Choi in 1920, which was famous as the first map showing directions and distances together and where the instrument is taken from Islamic sources which developed accounts This indicates that the instrument where an Islamic-based methods without foreign intervention.
The Ancient Egyptian "Merkhet" مِرخِت is considered to be the oldest astronomical invention. Ancient Egyptians called it "the instrument of knowing". It was a sighting tool invented by the Egyptians from the central rib of a palm leaf and was similar in function to an astrolobe. The Merkhet was used for aligning the foundations of the pyramids and sun temples with the cardinal points, and was usually correct to within less than half a degree. It was developed around 600 BC. and uses a string with a weight on the end to accurately measure a straight vertical line, much like a plumb bob. A pair of Merkhets were used to establish a north-south line by lining them up with the pole star. This allowed for the measurement of night-time hours as it measured when certain stars crossed a marked meridian on the sundial.
An early Egyptian Water Clock, dating to about 1500 B.C., was found among other items in the tomb of the pharaoh Amenhotep I of the 18th Dynasty, their creation is attributed to an inventor named Amenemhat. Early water clocks were bowl-shaped, with a small hole in the bottom. It is a little stand with a pot on the top of the stand and a pot at the bottom of the stand. The pot at the top of the stand had a hole drilled in the side. This pot was then filled with water and the water would flow out of the top pot down to the bottom pot. When the water was at a certain level, it was a certain time. Markings on the side, at even intervals, indicated the passage of every twelve hours. Water clocks were useful as people could accurately measure time, in all seasons, and even during the night. Another type of Water Clock had a float in the water. The float is connected with a 'hand' indicating the time on a board.  
Muslim astronomers produced an improved version of the Greek armillary sphere in the 8th century and they were the first to write about it in the treatise of Dhat al-Halaq or The instrument with the rings by Ibrahim al-Fazari (d.c. 777). Abbas Ibn Firnas (d.887) is thought to have produced another instrument with rings (armillary sphere) in 9th century.
The spherical astrolabe, a variation of both the astrolabe and the armillary sphere, was invented during the Middle Ages by astronomers and inventors in the Islamic world.[13] The earliest description of the spherical astrolabe dates back to Al-Nayrizi (fl. 892-902).
Muslim astronomers also independently invented the celestial globe, which were used primarily for solving problems in celestial astronomy. Today, 126 such instruments remain worldwide, the oldest from the 11th century. The altitude of the sun, or the Right Ascension and Declination of stars could be calculated with these by inputting the location of the observer on the meridian ring of the globe.
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