An erygmascope is a late 19th-century

electric Electricity is the set of physical phenomena associated with the presence and motion of matter that has a property of electric charge. Electricity is related to magnetism, both being part of the phenomenon of electromagnetism, as described by ...

lighting Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylig ...

apparatus designed for the examination of the strata of earth traversed by boring apparatus. It consisted of a very powerful incandescent lamp enclosed in a metallic cylinder. One of the two semi-cylindrical sides constitutes the reflector, and the other, which is of thick

glass Glass is a non-crystalline, often transparent, amorphous solid that has widespread practical, technological, and decorative use in, for example, window panes, tableware, and optics. Glass is most often formed by rapid cooling ( quenching ...

, allows the passage of light, which illuminates the strata of earth traversed by the instrument. The base, which is inclined at an angle of 45°, is an elliptical

mirror A mirror or looking glass is an object that reflects an image. Light that bounces off a mirror will show an image of whatever is in front of it, when focused through the lens of the eye or a camera. Mirrors reverse the direction of the im ...

, and the top, of straight section, is open in order to permit the observer standing at the mouth of the well, and provided with a powerful

spyglass Spyglass may refer to: * Another term for a hand-held refracting telescope A refracting telescope (also called a refractor) is a type of optical telescope that uses a lens as its objective to form an image (also referred to a dioptric tel ...

, to see in the

the image of the geological layers or of the structure of crystalline rocks. It somewhat resembles to a kind of inverted semi-

periscope A periscope is an instrument for observation over, around or through an object, obstacle or condition that prevents direct line-of-sight observation from an observer's current position. In its simplest form, it consists of an outer case with ...

aimed to look at earth downwards. The lamp is so mounted that its upwardly emitted rays are intercepted. The whole apparatus was suspended from a long cable, formed of two conducting wires, which winds around a windlass with metallic journals which are electrically insulated. These journals communicate, through the intermedium of two friction springs, with the conductors on the one hand and, on the other, with the

poles Poles,, ; singular masculine: ''Polak'', singular feminine: ''Polka'' or Polish people, are a West Slavic nation and ethnic group, who share a common history, culture, the Polish language and are identified with the country of Poland in C ...

of a portable

battery Battery most often refers to: * Electric battery, a device that provides electrical power * Battery (crime), a crime involving unlawful physical contact Battery may also refer to: Energy source *Automotive battery, a device to provide power t ...

. This permits of lowering and raising the apparatus at will, without derangement, and without its being necessary to interrupt the light and the observation. The erygmascope was described in an 1891 edition of the

Scientific American ''Scientific American'', informally abbreviated ''SciAm'' or sometimes ''SA'', is an American popular science magazine. Many famous scientists, including Albert Einstein and Nikola Tesla, have contributed articles to it. In print since 1845, it ...

Supplement; it is uncertain of the extent to which it was ever put to practical use.

Etymology

The

etymology Etymology ()The New Oxford Dictionary of English (1998) – p. 633 "Etymology /ˌɛtɪˈmɒlədʒi/ the study of the class in words and the way their meanings have changed throughout time". is the study of the history of the Phonological chan ...

of the term remains enigmatic, but could originate from a Greek word ''ήρυγμα'' meaning "trench". However, a shaft should be translated in Greek as ''πηγάδι'' (pegadi), and a

water well A well is an excavation or structure created in the ground by digging, driving, or drilling to access liquid resources, usually water. The oldest and most common kind of well is a water well, to access groundwater in underground aquifers. T ...

as ''φρέαρ'' (phrear). The origin of the suffix ''scope'' is classical for an

optical instrument An optical instrument (or "optic" for short) is a device that processes light waves (or photons), either to enhance an image for viewing or to analyze and determine their characteristic properties. Common examples include periscopes, microscopes, ...

: from ''σκοπεῖν'' (skopein), meaning to look at.

In art and popular culture

Sonic and visual artistic collaboration between Tracy Hill, artist, Ralph Hoyte, poet and writer, and Phill Phelps, musician, working in partnership with Lancashire Wildlife Trust and City of Trees. It symbolizes the curiosity of the three artists for looking beyond the surface whilst working on their opus ''Stratum''.Hill, T., Hoyte, R., & Phelps, P. (2020). Erygmascope.
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References

External links

* Boreholes Historical geology Optical devices Optical instruments Scientific equipment Stratigraphy Well logging {{geology-stub

Etymology

In art and popular culture

See also

References

External links