The Ether Monument , also known as The Good Samaritan , is a statue and fountain near the northwest corner of Boston 's Public Garden , near the intersection of Arlington Street and Marlborough Street.
41-537: It commemorates the use of ether in anesthesia . Its design has been attributed to the Boston architect William Robert Ware and to the sculptor John Quincy Adams Ward . It is 40 feet (12 m) tall and is the oldest monument in the public garden. The statue depicts a medical doctor in medieval Moorish-Spanish robe and turban—representing a Good Samaritan —who holds the drooping body of an almost naked man on his left knee. The doctor holds in his right hand
82-478: A CN from 48 to 50. Fuels with lower cetane number have longer ignition delays, requiring more time for the fuel combustion process to be completed. Hence, higher speed diesel engines operate more effectively with higher cetane number fuels. In Europe, diesel cetane numbers were set at a minimum of 38 in 1994 and 40 in 2000. The standard for diesel sold in European Union , Iceland , Norway and Switzerland
123-414: A cetane number of 0, but has been replaced as a reference fuel by 2,3,4,5,6,7,8-heptamethylnonane , which is assigned a cetane number of 15. All other hydrocarbons in diesel fuel are indexed to cetane as to how rapidly they ignite under compression, i.e. diesel engine conditions. Since hundreds of components comprise diesel fuel, the overall cetane number of that fuel is the average cetane quality of all
164-441: A cloth, suggesting the use of ether that would be developed in centuries to come. The anachronistic use of a Moorish doctor was probably intentional and served to avoid choosing sides in a debate that was raging at the time over who should receive credit for the first use of ether as an anesthetic. A handful of individuals had claimed credit for the discovery of anesthesia, most notably William T. G. Morton and Crawford Long . At
205-562: A common solvent for the Grignard reaction in addition to other reactions involving organometallic reagents. These uses exploit its basicity. Diethyl ether is a popular non-polar solvent in liquid-liquid extraction . As an extractant, it is immiscible with and less dense than water. Although immiscible, it has significant solubility in water (6.05 g/(100 ml) at 25 °C ) and dissolves 1.5 g/(100 g) (1.0 g/(100 ml)) water at 25 °C. Diethyl ether has
246-471: A fuel is defined by finding a blend of cetane and isocetane with the same ignition delay. Cetane has a cetane number defined to be 100, while isocetane's measured cetane number is 15, replacing the former reference fuel alpha-methylnaphthalene , which was assigned a cetane number of 0. Once the blend is known, the cetane number is calculated as a volume-weighted average, rounded to the nearest whole number, of cetane's 100 and isocetane's 15. Cetane number
287-498: A high cetane number of 85–96 and, in combination with petroleum distillates for gasoline and diesel engines, is used as a starting fluid because of its high volatility and low flash point . Ether starting fluid is sold and used in countries with cold climates, as it can help with cold starting an engine at sub-zero temperatures. For the same reason it is also used as a component of the fuel mixture for carbureted compression ignition model engines . Triethyloxonium tetrafluoroborate
328-539: A minimum cetane number of 70. In North America, most states adopt ASTM D975 as their diesel fuel standard and the minimum cetane number is set at 40, with typical values in the 42-45 range. Premium diesel fuel may or may not have higher cetane number depending on the supplier. Premium diesel often use additives to improve CN and lubricity , detergents to clean the fuel injectors and minimize carbon deposits, water dispersants, and other additives depending on geographical and seasonal needs. . California diesel fuel has
369-603: A minimum cetane of 53. Under the Texas Low Emission Diesel (TxLED) program there are 110 counties where diesel fuel must have a cetane number of 48 or greater, or else must use an approved alternative formulation or comply with the designated alternative limits. Neste MY Renewable Diesel sold in North America has a cetane number of 70+. Alkyl nitrates (principally 2-ethylhexyl nitrate ) and di- tert -butyl peroxide are used as additives to raise
410-503: A simpler, more robust approach to CN measurement than the CFR. Fuel is injected into a constant volume combustion chamber at approximately 575 °C and 310 psi (21 bar). The time between the start of injection and the recovery of the combustion chamber pressure to 310 psi (21 bar) is defined as the ignition delay. This measured ignition delay is then used to calculate the DCN of
451-407: A simpler, more robust approach to CN measurement than the CFR. Fuel is injected into a constant volume combustion chamber in which the ambient temperature is approximately 575 °C. The fuel combusts, and the high rate of pressure change within the chamber defines the start of combustion. The ignition delay of the fuel can then be calculated as the time elapsed between the start of fuel injection and
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#1732780853748492-488: A study published by William Procter, Jr. in the American Journal of Pharmacy as early as 1852 showed that there were differences in formulation to be found between commercial manufacturers, between international pharmacopoeia , and from Hoffman's original recipe. It is also used to treat hiccups through instillation into the nasal cavity. The recreational use of ether also took place at organised parties in
533-447: Is a colourless, highly volatile , sweet-smelling ("ethereal odour"), extremely flammable liquid . It belongs to the ether class of organic compounds. It is a common solvent . It was formerly used as a general anesthetic . Most diethyl ether is produced as a byproduct of the vapor-phase hydration of ethylene to make ethanol . This process uses solid-supported phosphoric acid catalysts and can be adjusted to make more ether if
574-449: Is an indicator of the combustion speed of diesel fuel and compression needed for ignition . It plays a similar role for diesel as octane rating does for gasoline . The CN is an important factor in determining the quality of diesel fuel, but not the only one; other measurements of diesel fuel's quality include (but are not limited to) energy content, density , lubricity, cold-flow properties and sulfur content. The cetane number of
615-488: Is an inverse function of a fuel's ignition delay, the time period between the start of ignition and the first identifiable pressure increase during combustion of the fuel. In a particular diesel engine, higher cetane fuels will have shorter ignition delay periods than lower cetane fuels. Cetane numbers are only used for the relatively light distillate diesel oils. For heavy (residual) fuel oil two other scales are used, CCAI and CII . Generally, diesel engines operate well with
656-509: Is defined by standard EN 590 . Since 1 January 2001 EN 590 demands a minimum cetane index of 46 and a minimum cetane number of 51. Premium diesel fuel can have a cetane number as high as 60. In Finland, premium diesel fuels sold by filling station chains St1 (Diesel Plus), Shell (containing GTL) and ABC (Smart Diesel) have a minimum cetane number of 60 with the typical value being at 63. Neste MY Renewable Diesel sold in Finland has
697-516: Is extremely flammable and may form explosive vapour/air mixtures. Since ether is heavier than air it can collect low to the ground and the vapour may travel considerable distances to ignition sources. Ether will ignite if exposed to an open flame, though due to its high flammability, an open flame is not required for ignition. Other possible ignition sources include – but are not limited to – hot plates, steam pipes, heaters, and electrical arcs created by switches or outlets. Vapour may also be ignited by
738-677: Is listed in the Table II precursor under the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances as well as substances such as acetone , toluene and sulfuric acid . The compound may have been synthesised by either Jābir ibn Hayyān in the 8th century or Ramon Llull in 1275. It was synthesised in 1540 by Valerius Cordus , who called it "sweet oil of vitriol" ( oleum dulce vitrioli ) –
779-535: Is located about a 15-minute walk from the site of the monument. The operating theater at MGH where the experiment took place was renamed the Ether Dome . It is now a National Historic Landmark. Several books have been written about this specific event. The monument was erected in 1868. It was restored and rededicated in 2006. As an outdoor monument in an area with a harsh climate, the structure has needed regular upkeep and repair. One source of revenue for upkeep of
820-566: Is prepared from boron trifluoride , diethyl ether, and epichlorohydrin : Diethyl ether is a common laboratory aprotic solvent . Diethyl ether is susceptible to formation of hydroperoxides . A cytochrome P450 enzyme is proposed to metabolize diethyl ether. Diethyl ether inhibits alcohol dehydrogenase , and thus slows the metabolism of ethanol . It also inhibits metabolism of other drugs requiring oxidative metabolism . For example, diazepam requires hepatic oxidization whereas its oxidized metabolite oxazepam does not. Diethyl ether
861-421: Is safely used in patients with shock as it preserves the baroreceptor reflex . Its minimal effect on myocardial depression and respiratory drive, as well as its low cost and high therapeutic index allows it to see continued use in developing countries. Diethyl ether could also be mixed with other anesthetic agents such as chloroform to make C.E. mixture , or chloroform and alcohol to make A.C.E. mixture . In
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#1732780853748902-441: Is typically supplied with trace amounts of the antioxidant butylated hydroxytoluene (BHT), which reduces the formation of peroxides. Storage over sodium hydroxide precipitates the intermediate ether hydroperoxides. Water and peroxides can be removed by either distillation from sodium and benzophenone , or by passing through a column of activated alumina . Due to its application in the manufacturing of illicit substances, it
943-566: The Lethe River (Λήθη, meaning "forgetfulness, oblivion"). However, Crawford Williamson Long is now known to have demonstrated its use privately as a general anesthetic in surgery to officials in Georgia, as early as March 30, 1842, and Long publicly demonstrated ether's use as a surgical anesthetic on six occasions before the Boston demonstration. British doctors were aware of the anesthetic properties of ether as early as 1840 where it
984-484: The 19th century and early 20th century ether drinking was popular among Polish peasants. It is a traditional and still relatively popular recreational drug among Lemkos . It is usually consumed in a small quantity ( kropka , or "dot") poured over milk , sugar water, or orange juice in a shot glass . As a drug, it has been known to cause psychological dependence , sometimes referred to as etheromania . Cetane number Cetane number ( cetane rating ) ( CN )
1025-479: The 19th century called ether frolics , where guests were encouraged to inhale therapeutic amounts of diethyl ether or nitrous oxide , producing a state of excitation. Long, as well as fellow dentists Horace Wells , William Edward Clarke and William T. G. Morton observed that during these gatherings, people would often experience minor injuries but appear to show no reaction to the injury, nor memory that it had happened, demonstrating ether's anaesthetic effects. In
1066-487: The 21st century, ether is rarely used. The use of flammable ether was displaced by nonflammable fluorinated hydrocarbon anesthetics. Halothane was the first such anesthetic developed and other currently used inhaled anesthetics, such as isoflurane , desflurane , and sevoflurane , are halogenated ethers. Diethyl ether was found to have undesirable side effects, such as post-anesthetic nausea and vomiting. Modern anesthetic agents reduce these side effects. Prior to 2005, it
1107-513: The base of the statue are inscriptions explaining the significance of the discovery of the use of ether as an anesthetic. There are four inscriptions, which include biblical quotations from Isaiah 28:29 and Revelation 21:4 : *To commemorate that the inhaling of ether causes insensibility to pain. First proved to the world at the Mass. General Hospital in Boston, October A.D. MDCCCXLVI Massachusetts General Hospital , where this procedure took place,
1148-418: The cetane number. Biodiesel from vegetable oil sources have been recorded as having a cetane number range of 46 to 52, and animal-fat based biodiesels cetane numbers range from 56 to 60. Dimethyl ether is a potential diesel fuel as it has a high cetane rating (55-60) and can be produced as a biofuel . Most simple ethers, including liquid ones, such as diethyl ether can be used as diesel fuels, although
1189-419: The components. High-cetane components have a disproportionate influence, hence the use of high-cetane additives. Cetane numbers are rather difficult to measure accurately, as it requires a special diesel engine called a Cooperative Fuel Research (CFR) engine. Under standard test conditions, the operator of the CFR engine uses a manual-wheel to increase the compression ratio (and therefore the peak pressure within
1230-509: The cylinder) of the engine until the time between fuel injection and ignition is 2.407 ms. The resulting cetane number is then calculated by determining which mixture of cetane ( hexadecane ) and isocetane (2,2,4,4,6,8,8-heptamethylnonane) will result in the same ignition delay. Another reliable method of measuring the derived cetane number (DCN) of diesel fuel is the Ignition Quality Tester (IQT). This instrument applies
1271-520: The fuel. The fuel's DCN is then calculated using an empirical inverse relationship to ignition delay. Because of the reproducibility, material cost, and speed of the IQT, this has been the definitive source for DCN measurements of fuels since the late 2000s. Another reliable method of measuring the derived cetane number of diesel fuel is the Fuel Ignition Tester (FIT). This instrument applies
Ether Monument - Misplaced Pages Continue
1312-468: The idea was disproved in about 1800. The synthesis of diethyl ether by a reaction between ethanol and sulfuric acid has been known since the 13th century. William T. G. Morton participated in a public demonstration of ether anesthesia on October 16, 1846, at the Ether Dome in Boston, Massachusetts . Morton had called his ether preparation, with aromatic oils to conceal its smell, " Letheon " after
1353-402: The lubricity can be of concern. Cetane is the hydrocarbon with chemical formulas C 16 H 34 and specifically the structural formula CH 3 (CH 2 ) 14 CH 3 . Also named n-hexadecane, it is an unbranched saturated alkane . Cetane ignites with a short delay under compression, and is assigned a cetane number of 100. Alpha-methylnaphthalene , which has a long delay period, was assigned
1394-745: The monument has been income from R. A. Ortega's Written in Granite: An Illustrated History of the Ether Monument , which is available only by making a donation of at least $ 100 through the Friends of the Public Garden which goes to a fund devoted to preserving the monument for the future. Diethyl ether Diethyl ether , or simply ether , is an organic compound with the chemical formula (CH 3 CH 2 ) 2 O , sometimes abbreviated as Et 2 O . It
1435-418: The name reflects the fact that it is obtained by distilling a mixture of ethanol and sulfuric acid (then known as oil of vitriol) – and noted some of its medicinal properties . At about the same time, Paracelsus discovered the analgesic properties of the molecule in dogs. The name ether was given to the substance in 1729 by August Sigmund Frobenius . It was considered to be a sulfur compound until
1476-401: The need arises: Vapor-phase dehydration of ethanol over some alumina catalysts can give diethyl ether yields of up to 95%. Diethyl ether can be prepared both in laboratories and on an industrial scale by the acid ether synthesis. The dominant use of diethyl ether is as a solvent. One particular application is in the production of cellulose plastics such as cellulose acetate . It is
1517-520: The number of distillation points that are used. These days most oil companies use the '4-point method', ASTM D4737, based on density and 10% 50% and 90% recovery temperatures. The '2-point method' is defined in ASTM D976 and uses just density and the 50% recovery temperature. This 2-point method tends to overestimate the cetane index and is not recommended. Cetane index calculations cannot account for cetane improver additives and therefore do not measure
1558-409: The start of combustion. The fuel's derived cetane number can then be calculated using an empirical inverse relationship to ignition delay. Another statistic used by fuel-users to control quality is the cetane index (CI), which is a calculated number based on the density and a distillation range of the fuel. There are various versions of this, depending on whether metric or Imperial units are used, and
1599-453: The static electricity which can build up when ether is being poured from one vessel into another. The autoignition temperature of diethyl ether is 160 °C (320 °F). The diffusion of diethyl ether in air is 9.18 × 10 m /s (298 K, 101.325 kPa). Ether is sensitive to light and air, tending to form explosive peroxides . Ether peroxides have a higher boiling point than ether and are contact explosives when dry. Commercial diethyl ether
1640-622: Was on the World Health Organization's List of Essential Medicines for use as an anesthetic. Ether was once used in pharmaceutical formulations. A mixture of alcohol and ether, one part of diethyl ether and three parts of ethanol, was known as "Spirit of ether" , Hoffman's Anodyne or Hoffman's Drops. In the United States this concoction was removed from the Pharmacopeia at some point prior to June 1917, as
1681-429: Was widely prescribed in conjunction with opium. Diethyl ether was preferred by some practitioners over chloroform as a general anesthetic due to ether's more favorable therapeutic index , that is, a greater difference between an effective dose and a potentially toxic dose. Diethyl ether does not depress the myocardium but rather it stimulates the sympathetic nervous system leading to hypertension and tachycardia. It