Editing Seismometer (section)

=== Early designs (1259–1839) ===
By the 13th century, seismographic devices existed in the [[Maragheh observatory]] (founded 1259) in Persia, though it is unclear whether these were constructed independently or based on the first seismoscope.<ref>{{Cite web |last=Szczepanski |first=Kallie |title=The invention of the Seismoscope {{!}} The Asian Age Online, Bangladesh |work=The Asian Age |access-date=2022-10-12 |url=http://dailyasianage.com/news/90282/?regenerate}}</ref> French physicist and priest [[Jean de Hautefeuille]] described a seismoscope in 1703,<ref name="Needham" /> which used a bowl filled with mercury which would spill into one of eight receivers equally spaced around the bowl, though there is no evidence that he actually constructed the device.<ref name=Oldroyd>{{Cite journal |doi=10.17704/eshi.26.2.h9v2708334745978 |volume=26 |last1=Oldroyd |first1=David |last2=Amador |first2=F. |last3=Kozák |first3=Jan |last4=Carneiro |first4=Ana |last5=Pinto |first5=Manuel |title=The Study of Earthquakes in the Hundred Years Following Lisbon Earthquake of 1755 |journal= Earth Sciences History|date=2007-01-01 |issue=2 |pages=321–370 |bibcode=2007ESHis..26..321O}}</ref> A mercury seismoscope was constructed in 1784 or 1785 by [[Atanasio Cavalli]],<ref>{{Cite journal |volume=13 |pages=1–21 |last=Ferrari |first=Graziano |title=Cultural and scientific value of seismology's heritage in Europe: why and how to preserve |journal=Cah. Cent. Europ. Geodyn. Seismol. |date=1997-01-01}}</ref> a copy of which can be found at the University Library in Bologna, and a further mercury seismoscope was constructed by [[Niccolò Cacciatore]] in 1818.<ref name=Oldroyd /> [[James Lind (naturalist)|James Lind]] also built a seismological tool of unknown design or efficacy (known as an earthquake machine) in the late 1790s.<ref>{{Cite book |last=Hart |first=Scott de |url=https://books.google.com/books?id=mIEOCwAAQBAJ&dq=earthquake+james+lind&pg=PA39 |title=Shelley Unbound: Discovering Frankenstein's True Creator |date=2013-07-22 |publisher=Feral House |isbn=978-1-936239-64-1 |pages=39 |language=en}}</ref>

Pendulum devices were developing at the same time. Neapolitan naturalist [[Nicola Cirillo]] set up a network of pendulum earthquake detectors following the 1731 Puglia Earthquake, where the amplitude was detected using a protractor to measure the swinging motion. Benedictine monk [[Andrea Bina]] further developed this concept in 1751, having the pendulum create trace marks in sand under the mechanism, providing both magnitude and direction of motion. Neapolitan clockmaker Domenico Salsano produced a similar pendulum which recorded using a paintbrush in 1783, labelling it a ''geo-sismometro'', possibly the first use of a similar word to ''seismometer''. Naturalist Nicolo Zupo devised an instrument to detect electrical disturbances and earthquakes at the same time (1784).<ref name=Oldroyd />

The first moderately successful device for detecting the time of an earthquake was devised by [[Ascanio Filomarino]] in 1796, who improved upon Salsano's pendulum instrument, using a pencil to mark, and using a hair attached to the mechanism to inhibit the motion of a clock's balance wheel. This meant that the clock would only start once an earthquake took place, allowing determination of the time of incidence.<ref name=Oldroyd />

After an earthquake taking place on October 4, 1834, [[Luigi Pagani]] observed that the mercury seismoscope held at [[Bologna University]] had completely spilled over, and did not provide useful information. He therefore devised a portable device that used [[lead shot]] to detect the direction of an earthquake, where the lead fell into four bins arranged in a circle, to determine the quadrant of earthquake incidence. He completed the instrument in 1841.<ref name=Oldroyd />