http://en.wikipedia.org/wiki/Accidental_(music)
It may be strange to think of "B-A-C-H" as a melody, given that the available musical notes we are familiar with include only A,B,C,D,E,F, and G
In the early days of European music notation (4-line staff Gregorian chant manuscripts), only the note B could be altered (i.e. have an accidental applied to it): it could be flattened, thus moving from the hexachordum durum (i.e. the hard hexachord: G-A-B-C-D-E) where it is natural, to the hexachordum molle (i.e. the soft hexachord: F-G-A-B♭-C-D) where it is flat.
The flat sign ♭ actually derives from a round b, signifying the B of the soft hexachord, that is, B flat (hence the name of the flat sign in French "bémol" from medieval French "bé mol" — modern French "bé mou" — or "soft b") and originally meant only B♭;
Both the natural sign ♮ and the sharp ♯ derive from a square b, signifying the B of the hard hexachord, that is, B natural (hence the name of the natural sign in French "bécarre" from medieval French "bé carre", earlier "bé quarre" — modern French "bé carré" — or "square b") and originally meant only B natural.
In the same way, in German music notation the letter B designates B flat while the letter H, which is actually a deformation of a square B, designates B natural.
Thus, in Johannes Sebastian Bach's homeland, his name is indeed a melody, more specifically, a cruciform melody, which Bach encoded into the last theme of the last fugue he ever wrote as a devotion to Christ.
What time of the day is noon?
Saturday, December 13, 2008
http://www.etymonline.com/index.php?search=noon&searchmode=none
Noon derives from the Latin nona hora meaning, "the ninth hour." Roman days began at six in the morning, so "noon" originally meant from 2 p.m. to 3 p.m.
When the word was borrowed into Old English as non it meant 3 p.m.
By the 12th century noon had come to refer to midday, and when prayer and meal times transitioned from 3.pm to 12 p.m., noon officially came to mean the sixth hour instead of the ninth.
Noon derives from the Latin nona hora meaning, "the ninth hour." Roman days began at six in the morning, so "noon" originally meant from 2 p.m. to 3 p.m.
When the word was borrowed into Old English as non it meant 3 p.m.
By the 12th century noon had come to refer to midday, and when prayer and meal times transitioned from 3.pm to 12 p.m., noon officially came to mean the sixth hour instead of the ninth.
Brannock Device
Tuesday, December 9, 2008
http://kottke.org/08/05/the-brannock-footmeasuring-device
If you have ever wondered about the device used at shoe stores to measure your feet, it is called a Brannock Device, and was patented in 1926 by Charles Brannock from Syracuse, New York. The initial prototype was based on models made using pieces from an Erector Set. Prior to the Brannock device shoe makers referred to wooden measuring sticks.
The Brannock device measures the length, width, and heel-to-ball length of the foot at the same time.
Brannock devices last up to 15 years (when the numbers wear off).
If you have ever wondered about the device used at shoe stores to measure your feet, it is called a Brannock Device, and was patented in 1926 by Charles Brannock from Syracuse, New York. The initial prototype was based on models made using pieces from an Erector Set. Prior to the Brannock device shoe makers referred to wooden measuring sticks.
The Brannock device measures the length, width, and heel-to-ball length of the foot at the same time.
Brannock devices last up to 15 years (when the numbers wear off).
Liquid Breathing
http://en.wikipedia.org/wiki/Liquid_breathing
Liquid breathing is a form of respiration in which a normally air-breathing organism breathes an oxygen-rich liquid (usually a perfluorocarbon) rather than breathing air.
Liquid breathing could be used in diving as an alternative to rigid diving suits and heliox/trimix. With liquid in the lungs, the pressure within the diver's lungs could accommodate changes in the pressure of the surrounding water without the huge gas partial pressure exposures required when the lungs are filled with gas. Liquid breathing would not result in the saturation of body tissues with high pressure nitrogen or helium that occurs with the use of non-liquids, thus would reduce or remove the need for slow decompression.
A significant problem, however, arises from the high viscosity of the liquid and the corresponding reduction in its ability to remove CO2. All uses of liquid breathing for diving must involve total liquid ventilation. Total liquid ventilation, however, has difficulty moving enough liquid to carry away CO2, because no matter how great the total pressure is, the amount of partial CO2 gas pressure available to dissolve CO2 into the breathing liquid can never be much more than the pressure at which CO2 exists in the blood. Therefore, assistance from a mechanical ventilator is required.
Liquid breathing could also be used in space travel to insulate astronauts against the effects of rapid acceleration. Liquid immersion provides a way to reduce the physical stress of G forces. Forces applied to fluids are distributed as omnidirectional pressures. Because liquids cannot be practically compressed, they do not change density under high acceleration such as performed in aerial maneuvers or space travel. A person immersed in liquid of the same density as tissue has acceleration forces distributed around the body, rather than applied at a single point such as a seat or harness straps. This principle is used in a new type of G-suit called the Libelle G-suit, which allows aircraft pilots to remain conscious and functioning at more than 10 G acceleration by surrounding them with water in a rigid suit.
Acceleration protection by liquid immersion is limited by the differential density of body tissues and immersion fluid, limiting the utility of this method to about 15 to 20 G[21] Extending acceleration protection beyond 20 G requires filling the lungs with fluid of density similar to water. An astronaut totally immersed in liquid, with liquid inside all body cavities, will feel little effect from extreme G forces because the forces on a liquid are distributed equally, and in all directions simultaneously. However effects will be felt because of density differences between different body tissues, so an upper acceleration limit still exists.
Liquid breathing for acceleration protection may never be practical because of the difficulty of finding a suitable breathing medium of similar density to water that is compatible with lung tissue. Perfluorocarbon fluids are twice as dense as water, hence unsuitable for this application.
Liquid breathing is a form of respiration in which a normally air-breathing organism breathes an oxygen-rich liquid (usually a perfluorocarbon) rather than breathing air.
Liquid breathing could be used in diving as an alternative to rigid diving suits and heliox/trimix. With liquid in the lungs, the pressure within the diver's lungs could accommodate changes in the pressure of the surrounding water without the huge gas partial pressure exposures required when the lungs are filled with gas. Liquid breathing would not result in the saturation of body tissues with high pressure nitrogen or helium that occurs with the use of non-liquids, thus would reduce or remove the need for slow decompression.
A significant problem, however, arises from the high viscosity of the liquid and the corresponding reduction in its ability to remove CO2. All uses of liquid breathing for diving must involve total liquid ventilation. Total liquid ventilation, however, has difficulty moving enough liquid to carry away CO2, because no matter how great the total pressure is, the amount of partial CO2 gas pressure available to dissolve CO2 into the breathing liquid can never be much more than the pressure at which CO2 exists in the blood. Therefore, assistance from a mechanical ventilator is required.
Liquid breathing could also be used in space travel to insulate astronauts against the effects of rapid acceleration. Liquid immersion provides a way to reduce the physical stress of G forces. Forces applied to fluids are distributed as omnidirectional pressures. Because liquids cannot be practically compressed, they do not change density under high acceleration such as performed in aerial maneuvers or space travel. A person immersed in liquid of the same density as tissue has acceleration forces distributed around the body, rather than applied at a single point such as a seat or harness straps. This principle is used in a new type of G-suit called the Libelle G-suit, which allows aircraft pilots to remain conscious and functioning at more than 10 G acceleration by surrounding them with water in a rigid suit.
Acceleration protection by liquid immersion is limited by the differential density of body tissues and immersion fluid, limiting the utility of this method to about 15 to 20 G[21] Extending acceleration protection beyond 20 G requires filling the lungs with fluid of density similar to water. An astronaut totally immersed in liquid, with liquid inside all body cavities, will feel little effect from extreme G forces because the forces on a liquid are distributed equally, and in all directions simultaneously. However effects will be felt because of density differences between different body tissues, so an upper acceleration limit still exists.
Liquid breathing for acceleration protection may never be practical because of the difficulty of finding a suitable breathing medium of similar density to water that is compatible with lung tissue. Perfluorocarbon fluids are twice as dense as water, hence unsuitable for this application.
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