Aspirin

The word "aspirin" is a very familiar word, but what exactly is aspirin? I suppose if one wants to learn more about aspirin, they should consult Bayer, the most well known maker of aspirin. Bayer has a separate aspirin site which provides a bit of history. Felix Hoffman, a chemist who worked for Bayer, first synthesized aspirin (acetylsalicylic acid or ASA) in a chemically pure and stable form in 1897. But according to the site, the story of aspirin actually started 3,500 years before that. The Egyptians used a concoction of dried myrtle leaves to treat pain. One thousand years later, Hippocrates was recommending the juice of the bark willow tree for pain. Both contain salicylic acid, the key component of aspirin. Bayer received the patent for aspirin and trademarked it under the name Aspirin® worldwide in 1899. Bayer lost the patent in 1917 allowing other companies to sell acetylsalicylic acid. Then in 1920, Bayer lost the trademark name "Aspirin". The courts in the US ruled that aspirin was a generic term, so that other manufacturers could sell ASA under the name aspirin. Aspirin is still trademarked in some countries, such as Canada and Germany, today. Where did the word aspirin come from? One story claims that the "a" stands for acetylsalicylic acid, the "spir" stands for spiraea ulmaria (the Latin name for the plant Meadowsweet from which one can extract salicylic acid) and the "in" is a chemical suffix use to indicate a manufactured ingredient.


Aspirin C₉H₈O₄



The site "Molecule of the Month, Aspirin" illustrates the chemistry of aspirin. The web page can be viewed in various ways (JAVA or CHIME-a chemical structure visualization program or plug-in). The chemical equations for making aspirin as well as its structure are given here.
But, is it hard to make aspirin? There are many sites that allow the reader to make their own. Chemistry Experiments is a good place to start. Lab 44 is the preparation of aspirin from salicylic acid and acetic acid (needs Adobe Acrobat Reader (a free download) to see it).



A wonderful site about aspirin that is worth a visit is the Aspirin Adventures . Its view point is different than that of a corporate site. Directed toward students, it goes through the process of discovering aspirin step by step, starting with observations and gathering information, then going on to formulating a hypothesis, testing and drawing conclusions.


Aspirin


Another really great fun site is The Reconstructors. This is one of those glorious interactive sites. It takes place in the future where much of the medical knowledge has been lost. The reader's job to recover it, rediscover aspirin and have fun at the same time. This might just turn out to be an all day job!

Lastly, how does aspirin work to relieve pain? The Howstuffworks web site unravels some of the secrets of the wonder drug aspirin.

Sundogs, Pillars or My!

Have you ever seen a "sundog"? How about a "pillar"? Well, maybe. What are they? Glad you asked. Basically, water droplets and ice crystals in the atmosphere refract and reflect light resulting in amazing optical phenomena. Are you ready to investigate further?


Image of a halo with sundogs.
 

"Sundogs" are also called "mock suns" or "parhelia" (from the Greek meaning with or beside the sun). The University of Illinois web site has a graphic illustrating how one is formed. Hexagonal plate-like ice crystals in the atmosphere, with their flat face horizontally oriented, refract or bend the sunlight 22 degrees leading to the formation of sundogs-bright spots on either side of the sun. The web abounds with pictures of sundogs (i.e. sundogs, January 28, Cool Atmospheric Phenomena and Sundogs over VLA). When light is refracted as it passes from one medium to another, a rainbow effect maybe observed due to dispersion. Therefore, it is not uncommon to see a sundog brightly coloured or all the colours of the rainbow! When sunlight is refracted by ice crystals randomly oriented, 22 degree halos occur. This time, light is refracted twice, once when entering and once when leaving the crystals. On Jan 11th, 1999, approximately 24 halos were observed at the South Pole. Was it a world’s record?

A "sun pillar" (or spectacular sun pillar) is a column or shaft of light reaching above or below the light source. In this case, plate or column shaped ice crystals reflect (or light pillars) the light. Pillars usually occur at sunset or sunrise, when the sun is low on the horizon. The web site reflection of light illustrates what happens when light is reflected. The reflected ray is the same colour as the incident ray. Pillars can be coloured, taking on the same colour as the light being reflected.

The sundogs and pillars do not just result from light refracted or reflected from the sun. One might chance to see a moondog or moon pillar or a Venus pillar (Venus Pillars and Dogs).