A turret clock or a public clock is a clock that is larger than a domestic clock and has a mechanism designed to drive a visual time indicator such as dials and or bells as a public amenity. Turret clocks specifically had mechanisms mounted high in a building often a purpose built tower such as churches, town halls, and other public buildings. Clocks were not referred to as turret clocks by clockmakers until recent times, often old clocks were recognised as turret clocks by their location.
A true turret clock has mechanical and latterly electrical power and therefore sits late in the history of timekeeping. The following timeline of clocks is not comprehensive but does indicate the placement of turret clocks.
Water clocks are reported as early as 4000 B.C. In Europe, water clocks were used from around 1000 A.D. to around 1350 A.D.
Mercury clocks used a drum with several chambers that were connected through calibrated holes. A rope was wound around the drum with a weight connected to one end. The weight pulling down turned the drum, and the mercury in the drum chambers resisted the turning motion by slowly flowing from one segment of the drum to the next, thus inhibiting the movement of the drum and making it turn at a more or less constant speed. The movement of the drum could be used to measure time.
Verge and foliot clocks
The third generation of mechanical clocks had a verge escapement and foliot and emerged in the 14th century. In the second half of the 14th century, over 500 striking turret clocks were installed all over Europe of which exists some form of documentation. It is possible that more clocks were made. This was the first time public clocks became easy to maintain, as water clocks needed more or less constant attention, so only wealthy institutions with enough manpower could maintain them. The verge and foliot mechanical clocks were relatively easy to maintain and so found their way into many churches, bell towers and town halls. This new technology spread quite fast (within a decade all over Europe).
The fourth generation of clocks were mechanical clocks with a pendulum, which was invented in 1657 by Christiaan Huygens. As the pendulum was more exact than the foliot, some foliot clocks were converted to pendulum. Again, this new technology was adopted quickly throughout Europe, with many clocks being converted (e.g. Castle Combe Clock, Salisbury cathedral clock, ...).
Electric turret clocks and hybrid mechanical/electric and were introduced in the late 19th century.
Some mechanical turret clocks are wound by electric motor. These still are considered mechanical clocks.
Table of early public turret clocks
This table shows some of the turret clocks which were installed throughout Europe. It is not complete and mainly serves to illustrate the rate of adoption. There are hardly any surviving turret clock mechanisms that date before 1400, and because of extensive rebuilding of clocks the authenticity of those that do survive is disputed. What little is known of their mechanisms is mostly gleaned from manuscript sources.
The "country" column refers to the present (2012) international boundaries. For example, Colmar was in Germany in 1370, but is now in France.
The verge and foliot escapement is thought to have been introduced sometime at the end of the thirteenth century, so very few if any of these clocks had foliot mechanisms; most were water clocks or in a few cases, possibly mercury.
|1283||United Kingdom||Dunstable||Priory||horologium||not known||Annals of the priory 1283 – Eodem anno fecimus horologium quod est supra pulpitum collocatum.||Probably a verge and foliot clock because it was mounted over the rood screen, where refilling a water clock would have been difficult, it has been proposed as the earliest known mechanical clock.|
|1284||United Kingdom||Exeter||Cathedral||Exeter cathedral clock||not known||grant made July 1284 to Roger de Ropford, bellfounder, to repair "orologium"||It is unlikely that this 1284 clock was a verge and foliot clock. The clock mentioned in the grant was probably a water clock. In 1423, a new clock was installed, which is probably the one from which remnants of the striking train can still be seen.|
|1286||United Kingdom||London||St Paul's Cathedral||Bartholomo Orologiario clock||not known||Compotus Bracini 1286||probably a water clock|
|1288 (?)||United Kingdom||Oxford||Merton College||not known||bursarial accounts "Expense orologii"||probably a water clock|
|1290||United Kingdom||Norwich||Norwich Cathedral||not known||Sacrist's roll 1290 "In emendacione orologio"||probably a water clock|
|1291||United Kingdom||Ely||Ely Abbey||not known||Sacrist's roll 1291 "pro custodia orologii"||probably a water clock|
|1292||United Kingdom||Canterbury||Christchurch cathedral||novum orolgium||not known||list of Prior Henry of Eastry's works "novum orologium mangum in Ecclesia"||probably a water clock|
During the fourteenth century, the emergence of the foliot replaced the high-maintenance water clocks. It is not known when that happened exactly and which of the early 14th century clocks were water clocks and which ones use a foliot.
The Heinrich von Wieck clock in Paris dating from 1362 is the first clock of which it is known with certainty that it had a foliot and a verge escapement. The fact that there is a sudden increase in the number of recorded turret clock installations points to the fact that these new clocks use verge & foliot. This happens in the years 1350 and onwards.
|1304||Germany||Erfurt||Benedict abbey St. Peter||"Schelle"||not known||consecration of "Petronella" and "Scolastica"||probably a mechanical alarm clock|
|1305||Germany||Augsburg||cathedral||not known||the "Domkustos" E. v. Nidlingen donates to the cathedral a "good and well adjusted clock"||probably a mechanical alarm clock|
|1306||United Kingdom||Salisbury||Salisbury cathedral||not known||composition concluded 26/8/1306 "Before the clock of the cathedral had struck one no person was to purchase or cause to be purchased ....||probably a water clock|
|1308||France||Cambrai||Cathedral||not known||mention of a clock, which was mended and equipped with moving figures in 1348, and fitted with a strike and an angel in 1398|
|1309||Italy||Milan||church St. Eustorgio||not known||mention of a metal clock, which was repaired in 1333 and 1555|
|1314||France||Caen||church St. Pierre||not known||mention of a striking clock|
|1316||Poland||Brzeg||town hall||not known||weights of the clock still present. New bell cast for clock 1370, replaced by new clock 1414|
|1322||United Kingdom||Norwich||Norwich cathedral priory||astronomical clock||Sacrist's roll of Norwich cathedral of 1322 to 1325 mentions the construction and installation of a clock which had a large astronomical dial and automata including 59 images and a choir or procession of monks||earliest detailed account of the organisation and of the craftsmen and materials involved in such a project|
|1325–1343||France||Cluny||collegiate church||not known||Petrus de Chastelux builds a new clock|
|1327||United Kingdom||St Albans||St Albans Cathedral||astronomical clock||drawings||Earliest clock for which there is detailed description of the escapement, this had a 'strob' escapement, a variation of a verge and foliot with two escape wheels.|
|1336||Italy||Milan||town||public striking clock with 24-hour dial||Annales Mediolanenses Anonymi||According to Bilfinger, this is the first mechanical striking clock and could have been made by de Dondi. This is the first time a clock is mentioned that strikes consecutive hours, e.g. once at 1, twice at two, etc. and that strikes day and night. As there are detailed descriptions of what the clock does, it was considered a novelty. Another candidate for the first mechanical clock.|
|1348–64||Italy||Padua||Castle Tower||Astrarium||astronomical clock with strike, verge and crown balance wheel||Il Tractatus Astarii||Giovanni de Dondi|
|1351||United Kingdom||Windsor castle||Great Tower||made in London by three Lombards (from Italy) who arrived 8/4/1352 and left on 24/5/1352|
|1351||Italy||Orvieto||clock tower next to the cathedral||striking clock with jacquemart|
|1352–54||France||Strasbourg||cathedral||astronomical clock. Three dials: bottom year dial with saint days, middle hour dial, top hourly procession of 3 kings before Maria, at the top a crowing rooster.||taken out of service in 1547|
|1356||Italy||Bologna||castle tower||striking clock|
|1356–61||Germany||Nuremberg||Frauenkirche||striking clock with display of the prince-electors around the Kaiser||substituted in 1508/09 with the clock on the outside of the Frauenkirche|
|1359||Germany||Frankenberg||Pfarrkirche||astronomical clock with the three kings around the Virgin Mary|
|1359||Italy||Sienna||city tower||Bartolo Giordi mounts a clock on the city tower|
|1361||Germany||Frankfurt||cathedral||astronomical clock||made by Jacob, improved 1383, taken out of service 1605|
|1361||Germany||Munich||city tower||mention of existing clock|
|1362||Belgium||Brussels||St Nicholas church||not known||mention of a turret clock|
|1362||Italy||Ferrara||castle tower||clock mounted on castle tower|
|1362–70||France||Paris||Tour de l'Horloge||verge and foliot striking clock||Froissart's poem "L'Horloge amoureuse" mentions the clock. Drawing exists.||a drawing of the going train shows a door frame construction. Built by the German Heinrich von Wiek.|
|1364||Germany||Augsburg||Perlachturm||striking clock||clock was repaired in 1369 and a quarter strike was added in 1526|
|1365–67||United Kingdom||London||Westminster Palace||not known||a clock tower on the north wall at the end of the King's Garden opposite the entrance to the great hall was begun in 1365 and finished in 1367.|
|1366||Spain||Toledo||cathedral||goldsmith Gonzalo Perez supplies a clock for the tower of the cathedral|
|1366–68||Switzerland||Zurich||Petersturm||striking clock||Master Chunrad von Cloten builds a striking clock for the Petersturm|
|1366||United Kingdom||Kent||Queenborough Castle||striking clock|
|1367||Poland||Wroclaw||town hall||mention of existing town hall clock|
|1368||United Kingdom||Kings Langley||Kings Langley Manor||striking clock||Edward III provided a patent giving safe conduct to three Flemish clockmakers. These people probably built the clock.||after the expiry of the patent in 1369 John Lincoln was appointed as Royal clock keeper.|
|1368||Poland||Opava||Town council signs contract with master Swelbel to furnish a clock|
|1369||Germany||Mainz||Pfarrkirche St. Quentin||striking clock|
|1370||France||Colmar||cathedral tower||striking clock|
|1370||Poland||Swidnica||the town council engages the services of master Swelbel to furnish a clock, that is as good or better than the clock at Wroclaw.|
|1371||United Kingdom||York||York Minster||striking clock||Fabric Rolls of York Minster record purchase of a new clock made by John Clareburgh in 1371 or £13 6s. 8d.|
|1372||Belgium||Golzinne||castle||striking clock||Louis Defiens furnishes a striking clock for the castle|
|1372–73||France||Strasbourg||cathedral||striking clock||Heinrich Halder mounts a striking clock on the cathedral tower|
|1376||Belgium||Sens||a clock with several bells is manufactured|
|1376||France||Beauté-sur-Marne||castle||Pierre de S. Béate furnishes a clock for the castle|
|1377||Belgium||Dendermonde||belfry||Jan van Delft manufactures a clock for the belfry|
|1377||France||Valenciennes||town hall||the town hall clock is replaced and fitted with 2 striking figures|
|1377||Italy||Vicenza||town hall||striking clock||Master Facius Pisanus manufactures a new striking clock for the town hall|
|1377||Belgium||Ypres||belfry||striking clock with several bells|
|1380||Germany||Bamberg||cathedral||clock installed at the cathedral|
|1380||France||Nieppe||castle||Pierre Daimville engaged to furnish a metal clock weighing 300 pounds for the castle, which already has an existing clock|
|1382–84||Germany||Hamburg||Nikolaikirche||striking clock||Blacksmith Schinkel furnishes a public striking clock for the Nikolaikirche|
|1383–84||France||Dijon||Notre-Dame||striking clock||the clock taken from Courtrai in Belgium in 1382 is mounted on the tower of Notre-Dame|
|1383||Germany||Fritzlar||mention of a turret clock|
|1383||France||Lyon||eglise St. Jean||striking clock||mention of a small striking clock at St. Jean|
|1384||Germany||Friedberg||striking clock||Wernher von Ilbenstedt manufactures a striking clock|
|1384||Germany||Minden||cathedral||mention of the cathedral clock being repaired|
|1385||Switzerland||Luzern||Graggenturm||striking clock||Blacksmith H. Halder furnishes a striking clock for the Graggenturm and leaves a manual for the treatment of the clock||The operating instructions for this clock were written down, and clearly refer to a verge and foliot clock. the "frowen gemuete [happy/agitated mood]" is the foliot.
English translation: If you want to adjust the clock and put it forward or backward, disengage the foliot from the escape wheel and hold the escape wheel safely in your hand, or the weight will lose itself which might damage the clockwork. As you are now holding the escape wheel, use it to either let down the weight if you want to shorten the hour, or, if you want to lengthen the hour, pull it up, all in such a way that you are not doing too much nor too little and that you observe it well on the count wheel. If you also pull down the [lute] wheel, you can set the count wheel to whichever hour you want, be it I, II, III, etc. If you feel that the foliot is going too fast, lift the lead weights away from the wheel, and if it is too fast, move them towards the wheel, therewith you hinder or further it, as you like it. You might want to make it faster during the night, as the clock work goes for most of the night slower than during the day. Keep an eye on both weights, and if it happens that they have hardly any more rope, wind them up again, which you can do whenever you want to.
|1386||Germany||Braunschweig||Katharinenkirche||Marquard furnishes a clock for the Katharinenkirche. The cathedral already had a clock in 1346|
|1386||United Kingdom||Salisbury||Cathedral||Salisbury cathedral clock||Striking Clock||Deed||might not be the clock on display at the cathedral|
|1386||Germany||Wurzburg||cathedral||clock at the cathedral mentioned|
|1388||France||Béthune||belfry||striking clock||The citizens of Bethune want to re-construct the existing belfry and put up a clock. "... pour pouvoir reconstruire leur beffroi
qui etait a present moult demolis et venus k ruyne et en peril de keir (tomber) de jour en jour et en obtenir l'autorisation d'y placer une orloge pour memore des heures de jour et de nuit sicomme il est en pluseurs autres lieux et bonnes villes du paus environ".
|We have a reference here on how common turret clocks have become – they refer to " a clock to remind of the hours of the day and the night as it is now common in other places and good towns ...". This is also a reference that shows that turret clocks struck the time day and night.|
|1388||Germany||Magdeburg||cathedral||striking clock||mention of a striking clock at the cathedral|
|1389||France||Rouen||belfry||striking clock with quarter strike||Jehan de Felains paid 70 Livres for a clock with a quarter strike for the belfry|
|1391||France||Metz||cathedral||striking clock with quarter strike||Manufactured by Heinrich von Wieck|
|1392||France||Chartres||striking clock||clockmaker and blacksmith Philibert Mauvoisin instructed to make a striking clock resembling the one at the Paris castle|
|1392||Germany||Hanover||market church||blacksmiths Meistorpe and Hans Krieten furnish a clock for the market church|
|1392–93||United Kingdom||Wells||Wells Cathedral||striking clock||if this is the clock now shown at the British Museum in London is questionable|
|1394||Germany||Stralsund||Nikolaikirche||astronomical clock||Nikolaus Lilienfeld furnishes a clock for the Nikolaikirche|
|1395||Germany||Doberan||church||astronomical clock||an astronomical clock similar to the one in Stralsund is put up at the church|
|1395||Germany||Speyer||Altburgtor||striking clock||a striking clock is reported at the Altburgtor and at the Predigerkirche|
|1398–1401||Germany||Villingen||astronomical clock||Master Claus Gutsch manufactures an astronomical clock after the Strasbourg clock.|
It becomes apparent that even small towns can afford to put up public striking clocks. Turret clocks are now common throughout Europe.
No surviving clock mechanisms (apart from the claims from Salisbury and Wells) known from this era.
|Wikimedia Commons has media related to Turret clocks.|
- Graggenturm of Luzerne, instructions:"Als du das urleyn wiltt richten und das nider gewe uf ziehen oder ablan, so tuo das frowen gemuete von dem rade oder us dem rade, do es inne gat, und behab das kamprat sicher in der hant, oder das gewege verlieffe sich alsbalde, das das werg vil lichte brecht. Und so du das kamprat also in der hant hoebest, do mitte macht du denne das nider gewege abe lan, ob du die stunde wilt kúrzen, wilt du aber die stunde lengern, so zúhes uf, alles in solicher masse, das du nút ze vil noch ze wenig tuest und des nimmest du wol war am zalrade. Wenne du ouch das lúte rat nider zúhest, so macht du das zal rat setzen uf wele stunde du wit, es sie uf i, ii, iii, etcetera. Und so das frowen gemuete ze balde gat, das dich dunke, so hebe die bli kloetzli vaste hin us an das redelin, und so es ze trege gat, so henke si hin in an das redelin, hie mitte macht du es hindern und fúrdern, wie du wit. Sunderlich darf es ze nacht wol fúrderndes, wand das werg den merteil ze nacht treger got denne tages. Der gewege nim beder war, so si sich ergangen habent, das si schiere nút me seilen habent, so zúch si wider uf, dis macht du tuon , wenne du wit."
- C F C. Beeson English Church Clocks London 1971
- Christopher McKay (Editor) The Great Salisbury Clock Trial, Antiquarian Horological Society Turret Clock Group, 1993
- Alfred Ungerer Les horloges astronomiques et monumentales les plus remarquables de l'antiquité jusquà nos jours, Strasbourg, 1931
- Ferdinand Berthoud Histoire de la mesure du temps par les horloges, Imprimerie de la Republique, 1802
- Gustav Bilfinger Die Mittelalterlichen Horen und die Modernen Stunden, Stuttgart, 1892
- F.J. Britten Old clocks and their makers:an historical and descriptive account of the different styles of clocks of the past in England and abroad : with a list of over eleven thousand makers, London, 1910
- Ernst Zinner Aus der Frühzeit der Räderuhr. Von der Gewichtsuhr zur Federzuguhr München, 1954