What keeps fire hydrants from freezing in winter?

The fire hydrants are a common sight in cities, especially in shopping areas. They are a blessing to the firefighters. The hydrants help the firefighters to access the underground water through hoses.

The hydrants, as we see them today, have been around for about two centuries. Frederick Graff Sr., chief engineer of the Philadelphia Water Works, is credited with the invention of the current fire hydrants at the turn of 19th century. This design is known as pillar or post type. He is said to have obtained the first patent for a hydrant, but it is unconfirmed because the United States patent office itself was decimated in a fire in 1836.

Hydrants are of two types: wet barrel hydrants and dry barrel hydrants. The one that was developed by Graff was wet barrel kind which had the main valve on top of it. It had a constant flow of water into the hydrant. The problem with wet barrel hydrants is that they can be useful only in warmer climates. It is the dry barrel hydrant that is used in areas very much affected by cold.

In dry barrel hydrants, the water doesn't always flow into the hydrant. Only a small part will be above the ground. This is used to connect the hose to the hydrant when necessary. These hydrants would have two valves: the main valve and the drain valve. Only one valve will be open at a time. The main valve allows water flow into the hydrant while the other helps to drain out the water into ground after the use. Unlike the wet barrel design, in which the main valve is above the hydrant, the valve connecting the hydrant to the water main is very much deep under the ground in dry barrel hydrants. The design doesn't allow the water to remain in the hydrant. Since there is no water in the hydrant, there is nothing to freeze.

The water pipe and valve in dry barrel hydrants will be under the frost line, the maximum depth to which the ground freezes in winter. The part above the ground is a simple metallic pipe. Another advantage with the design is that even if an accident takes place, it doesn't result in a leakage of water. However, dry barrel hydrants are not completely free from hazards. In unusually cold weathers the frost line can move much deeper and cause damage to the water pipes.


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Why do some people have dimples?

Is there anyone who doesn't admire dimples? Dimples are considered by many to be one of the attractive features regarding beauty. That small dip that appears on cheek when one smiles gives him or her an aura of childlike innocence and it is regarded to be sweet. But would anyone believe if they were told that dimple is actually a genetic defect?

Alternatively known as gelasin, a dimple is a small indentation on the flesh. Scientists had considered it to be a dominant genetic trait till recently. That is, if the parents have dimples, the children are supposed to inherit it. However, that theory is out of favour now. Researchers say that there is no strong evidence to suggest that dimple is dominant trait but is an irregular one. If both parents have dimples, the children have 50%-100% chance to inherit them. Dimples can appear on both cheeks, or on one. Some have dimples on birth, while others develop later.

There are two kinds of dimples: cheek dimples and chin dimples. While the cheek dimples make their presence when the person makes a facial expression, the latter is a constant one. The dimple on chin is generated from a cleft in the bone of chin.

The cheek dimple is actually a deformity on the facial muscle. There are two different views on the cause of it. One is that dimple is formed by shortened muscles around the mouth. When the face moves, it draws tightly to form a dent on the skin. However, it is also caused by structural variations in the muscle known as zygomaticus major. It is usually a large muscle and its bifid structure causes dimples.

The formation of dimple takes place during the embryonic development. There are also temporary dimples, caused by excessive fat on the face. It is a sign of unhealthy diet, and will disappear with the loss of that fat.

Many people concerned with beauty have longing for that small dent on the face. The belief that one can create a dimple is widespread, underscored by the many tips and tricks going around both online and offline. If that is not enough, there was a dimple machine invented in 1936, by Isabella Gilbert from New York which is regarded now as one of the most ridiculous inventions ever. There is no way one can make a permanent dimple on the cheek so far, but that doesn't discourage people from trying. Many opt for surgery and piercing, but those don't exactly produce natural dimples.


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What is the origin of the word "buck" for dollar?

It is never easy to trace the etymology of the words we use every day, in any language. Some of the words would have fascinating stories to tell of their origin and others might seem to have originated out of nothing. If you are familiar with the American way of life, you would know that the U.S. dollar is commonly referred to as “buck”. Although the word is thrown around casually, few seem to be concerned about its origin. There had been attempts to ascribe the origin of the term to the racist history of the country, claiming that the term was used to mention young male slaves, though there is no plausible evidence.

The first U.S dollar was minted in 1792, following the Coinage Act. However, the available evidence traces the history of using “bucks” for denoting the dollars back to a practice before 18th century. In those days, the deerskin, or buckskin, was the prime medium of economic transactions, especially along the frontier areas. Those were the years of revolution, and money was hard to obtain. The buckskin was very valuable, and was used to represent the value of other things. They were exchanged for other commodities and people used the term buck to denote those skins. The buckskin featured prominently in the transactions with the Indians as well.

One of the earliest references to the use of bucks in terms of money can be found in a journal by Conrad Wieser during his travel through the present day Ohio, in which he mentions that someone was robbed of the value of 300 bucks. There is another reference from the same year, which mentions trading a cask of whiskey to native Indians, which is worth 5 bucks.

It is debatable whether a buck meant a single deerskin. Various observations have emerged, explaining that it was according to the quality of the skin. In the case of low quality deerskins, it took a few to form one buck. It seems that the skins of other animals were also in use, but deerskin was the most valuable. After the introduction of state currency, the use of buckskin as a medium of exchange gradually ceased to exist. However, the term buck stayed in popular culture, so did its association with the money.


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What is the origin of the phrase “beer belly”? Does beer really cause pot belly?

Beer belly is a popular colloquial term for the abdominal obesity. It is also known in various names like potbelly, beer gut and beer pot. Its origins are unknown, although it might have stemmed from the tendency of habitual drinkers develop a protruding belly over time, especially of old men. But does beer actually cause pot belly?

Despite the popular assumptions, there is no scientific evidence to support the claim that beer in particular causes any kind of obesity, at least no more than the other alcoholic beverages we consume. Beer drinkers come in all sizes and shapes. There are many beer drinkers with athletic build. A beer belly is much likely to be noticed in people leading sedentary lives than those who do physical labors.

Beer is like its relative beverages. None of them contains fat. They are actually rich in calories but these calories come from alcohol, which is a carbohydrate. Different beverages contain varying amount of calories, and a drinkers calorie intake purely depends on the consumption and the amount of calories contained in the particular beverage.

The primary reason for beer belly is the large amount of caloric intake. Any type of calories can result in a fat midsection. And, alcohol in particular can trigger the formation of a pot belly since the liver burns alcohol before the fat. A normal beer contains about 150 calories. Many of us drink too much beer in one go, and that means a large caloric intake as well as reduction in burning of fat. Add to it the fact that alcohol increases appetite. We tend to eat more food when consuming alcohol as well. Any excess calories would be stored as fat in our body. It naturally leads to overweight and potbelly. It is more noticeable in men because they tend to store the fat in midsection while the women store the excess fat in arms, thighs, buttocks and bellies combined. It is more prominent in older people as well, since they have less caloric need and are less active making weight gaining easier.

So, the beer is not alone to blame that protruding belly of yours. There are a lot of factors playing a major part, like uncontrolled diet, alcohol consumption in general, hormone imbalance, lack of exercise and even stress. Balance is the keyword here. With a balance in diet and exercise, one need not worry about beer belly and its consequences.


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What does SOS stand for? When was the first SOS message relayed and by whom?

Sea voyages are pretty risky affairs. Before the late 19th century they were more so because the ships at sea were pretty much isolated since there was no means of communication with the land. It took some time to know if a ship had got into an accident or so.

With the invention of wireless telegraph, it became possible to establish a communication system between the ships and the land. The telegraph system uses Morse code for communication which is a way of representing letters using dots and dashes. There were developed some distress signals to inform if the ship was in any trouble and in need of assistance. The first use of telegraph for assistance was in 1899, when two ships collided with each other near the English coast. The SOS message is such a distress signal, developed in early years of 20th century.

The predecessor of SOS was CQD, introduced by Marcony Company. It was interpreted as short for 'Come Quick Danger' but was actually derived from the code for general calls in land wire, CQ. The D meant distress. The signal translated to 'All stations, Distress'. CQD was favored by many even after the introduction of SOS, and it stayed for years until fading into history.

SOS is often interpreted by the public to mean phrases like 'Save Our Ship', 'Save Our Souls' and 'Send Out Succor', however it is not so. It has no specific meaning, as attested by the Marconi Yearbook of Wireless Telegraphy and Telephony itself in 1918. The SOS was selected as the code simply for its easy representation. The signal is three dots, followed by three dashes and three dots again, without letter spacing. It is also the only Morse code signal with nine elements.

Even though it was popularized by Marconi Company, SOS was first introduced by Germany in 1905. It was adopted as the standard distress signal by the international maritime community at the second International Radiotelegraphic Convention in Berlin in 1906, effective from 1st July, 1908.

Another popular misconception among public is that Titanic was the first ship to send an SOS message. However, it is a myth since the first SOS transmission was on June 10, 1909, from RMS Slavonia. Titanic, upon its sinking in 1912, used both CQD and SOS signals intermixed. Later, with the progress of technology, new signals and better communication methods arrived. SOS continued to be a standard distress signal until its replacement in 1999 with the Global Maritime Distress and Safety System.


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When and where did slavery start?

Over thousands of years of the history of humans, we have been witness to many abominable things. Slavery certainly ranks high among them. It has robed millions of their happiness and dignity, and led them to subjugation under other members of their own species.


Slavery has a very long history. It traces its birth back to prehistoric times and has been there in almost every civilization from ancient times. In many cultures, it was legal and slaves were considered properties of their masters. The social status of slaves varied according to places and time.

Slavery began with the formation of civilizations. Early humans were hunters and nomads, who had no use of slaves. With the dawn of civilizations, new jobs were created and workers were needed. Slavery began with the workers hired for cheap wage. Wars were one of the primary sources of slaves. The captives of war were considered slaves and were made to work for meager food and accommodation. Debts, selling of children by poor families, punishments and all created more slaves. In many places, children born to slave mothers were recognized as slaves as well.

It is not possible to pinpoint the exact place and time when slavery started. Written reference to slavery has been found in the Code of Hammurabi, daring back to 18th century BC. The ancient civilizations of Mesopotamia, Egypt and Indus Valley were all familiar with slavery, though the fraction of slaves was very small.

The earliest known slave society emerged in Greece. It was particularly strong in the state of Athens. Most of the slaves were domestic servants. The male slaves did the outdoor works while the females were retained as concubines or maids. From there slavery spread to Roman Empire and other civilizations. The expansion of Roman Empire triggered more wars and created new slaves. In the last two centuries BC, more than half of the Roman population was slaves. It was also when slaves began revolts, most famous of those led by Spartacus.

Slavery spread to Entire Europe and was strong in the middle ages. With the beginning of colonization it reached Africa and America and parts of Asia. The Arab world also endorsed the slave culture since 8th century.

From 18th century, the world witnessed many abolition movements which resulted in the ban of slavery. Many European countries banned the slave system. In 1863, American president Abraham Lincoln issued his historical Emancipation Proclamation.


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Where there ever Black slave owners?

While the modern history of slavery is built on racial discrimination and superiority complex, there are some unpopular truths that many have forgone to acknowledge. While the slave tradition was certainly fertilized by the White people, there were numerous free Blacks who involved themselves in buying and selling slaves in America.

The evidences suggest that Blacks, or African-Americans as they are called now, were involved in slave trade, not just as victims but also as perpetrators, from at least 17th century. Throughout the American civil war, there were myriad Black masters who owned slaves. Historians have been in unceasing arguments over the motivations of these masters to trade their own people. Some claim that the free Blacks bought slaves in order to protect them from the atrocities they would otherwise suffer under their White masters. The opposing argument is that they were motivated by the same things as the Whites: exploitation.

Interestingly, there is an element of truth in both arguments. There were some Black masters who bought slaves with philanthropic intentions while there were others who were exactly like their White counterparts. All of the 13 American states had free Blacks who owned slaves, though very few official records exist about them. One of the earliest records is about the couple Anthony Johnson and Mary Johnson of Virginia, who approached court in 1654 to obtain the service of their indentured Black servant John Castor. One particular name that was notorious among the slave owners is of Nat Butler, a farmer from Maryland who made slave trade a regular affair. The slave ownership reached its peak among the Blacks around 1830s. Most of them owned one or two slaves, most likely a family member to protect them from outside humiliation. There were a number of people who owned numerous slaves, like Antoine Dubuclet, William Ellison, John Carruthers Stanly, Justus Angel and Andrew Durnford who all had more than 50 slaves.

During the civil war, a group of Black slave owners in New Orleans even pled their allegiance to the Confederacy and formed their own private army to defend it. This militia had 440 men initially and was termed as Native Guards of Louisiana by the state governor. At its peak, it had some 1,000 guards. When Louisiana fell to the Union army, some of these guards changed sides and formed a new militia to fight for the Union. However, as the civil war progressed, the number of Black slave owners saw a decline and only a small fraction of the total slave owners were Blacks.


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