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TODAY IN HISTORY

    THE FIRST IRON LUNG
    July 29, 1927 - United States

    (Electric Respirator) was installed at Bellevue hospital in New York for the post war polio epidemic. The first iron lung was developed at Harvard University by Phillip Drinker and Louis Agassiz Shaw built with two vacuum cleaners. The iron lung is a negative pressure machine which surrounds the patient's body except for the head, and alternates a negative atmospheric pressure with the ambient one, resulting in rhythmic expansion of the chest cage (and thus inhalation) in response to the negative extra thoracic pressure. During periods of ambient extrathoracic pressure, the lungs deflate. This type of machine is rarely used today.

    AMERICA'S FIRST ASPHALT PAVEMENT
    July 29, 1870

    Was laid in Newark, N.J. Previously, coal tar was used for many pavements laid in the 1860s. The first recorded asphalt pavement in the U.S. was a sand mix placed in front of the City Hall in Newark, N.J., in 1870. Edmund J. DeSmedt, a Belgian chemist (who became the inspector of asphalt and cements for the District of Columbia) held a U.S. patent for this asphalt paving method, granted on 31 May 1867. In that century most roads, even in cities, were wide dirt pathways, severely affected by weather. Smooth surfaced asphalt roads originally were for the benefit of bicyclists. By 1904, only 141 miles were surfaced, but commonplace by 1916. Natural asphalt deposits were originally used, but almost all of the asphalt used commercially is now made from petroleum.

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  • The Revolution
    by John Adams

    "...The Revolution was effected before the War commenced. The Revolution was in the minds and hearts of the people; a change in their religious sentiments of their duties and obligations. This radical change in the principles, opinions, sentiments, and affections of the people, was the real American Revolution...."
  • The wealth of the nation
    by Earth Day, Gaylord Nelson

    "...The wealth of the nation is its air, water, soil, forests, minerals, rivers, lakes, oceans, scenic beauty, wildlife habitats and biodiversity that'as all there is. That'as the whole economy. That'as where all the economic activity and jobs come from. These biological systems are the sustaining wealth of the world...."

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  • Cancer Facts & Figures
    about Besides Lung Cancer

    Besides lung cancer, tobacco use also increases the risk for cancers of the mouth, lips, nasal cavity (nose) and sinuses, larynx (voice box), pharynx (throat), esophagus (swallowing tube), stomach, pancreas, kidney, bladder, uterus, cervix, colon/rectum, ovary (mucinous), and acute myeloid leukemia. Salary
    about Steve Jobs

    Steve Jobs' annual salary was $1, just enough to keep company health benefits.

Directories and Search Engines :

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A good placement in the web directory maximizes the chance of visibility your site.

ARTICLE CONTENT :

Search engine is the term with which we are accustomed with very much. But the web directory is not that same. The web directories are older than search engines according to the time of their invention. There are some similarities and some differences between search engines and web directories. Web directories were present before the invention of search engine. The popularity of web directories were also came before the search engines. Web directories are nothing but a directory form where different types of resources and information are gathered by human hand.

The resources are here various kinds of link which are arranged according to their names. It can be arranged alphabetically, name wise and differently. It is exactly like a directory setting where various collections of links to various site are collected or arranged maintaining some attributes and qualities. Web directories offer a search but it is not like the search of a search engine. If the search directories do not offer the search facility of some kind then it would be completely impossible to browse thousands of pages for computers. But it can not be a search engine in two ways.

Fundamentally most web directories are different from search engines as directories are edited by humans and URLs here are not collected by spiders but they are submitted by the site owners. The main advantage of Web directories is that no matter how clever spiders become, when there is a human to view and check the pages, there is a lesser chance that pages will be classified in the wrong categories. And the disadvantage with this difference is that the lists in web directories are sometime outdated because if there is no human being to edit and submit the directories then it will be outdated. You have to edit and check the submission unless it will be not working. But this is not that bad because search engines also deliver pages that do not exist anymore. And the other disadvantage with it is that sometimes you might have to wait half a year before being included in a search directory. Mainly these differences are occurred because it is not automatically maintained or mechanically maintained.

On the other hand the search engines are automatically maintained with out any help of human hand. As in web directories there is no hand of spiders that is why anyone should go there and submit the URLs to the search directories. The job of search engines is much easy and automatic but the job of web directories is not automatic but manually done. Once you are included in a particular directory, in most cases you can stay there as long as you wish to and wait for people and search engines to find you. The fact that a link to your site appears in a respectable Web directory is good because first, it is a backlink and second, you increase your visibility for spiders, which in turn raises your chance to be indexed by them.

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