Look to many of history's cultural symbols, and there you'll find an ancestor of Frosty, the snowman in the movie Frozen. It appeared on some of the first postcards, starred in some of the earliest silent movies, and was the subject of a couple of the earliest photos, dating all the way back to the 1800s. I discovered even more about one of humanity's earliest forms of life art during several years of research around the world.

    For example, snowmen were a phenomenon in the Middle Ages, built with great skill and thought. At a time of limited means of expression, snow was like free art supplies dropped from the sky. It was a popular activity for couples to leisurely walk through town to view the temporary works of chilly art. Some were created by famous artists, including a 19-year-old Michelangelo, who in 1494 was appointed by the ruler of Florence, Italy, to build a snowman in his mansion's courtyard.

    The Miracle of 1511 took place during six freezing works called the Winter of Death. The city of Brussels was covered in snowmen—an impressive scene that told stories on every street corner. Some were political in nature, criticizing the church and government. Some were a reflection of people's imagination. For the people of Brussels, this was a defining moment of defining freedom. At least until spring arrived, by which time they were dealing with damaging floods.

    If you fear the heyday of the snowman has passed, don't worry: I've learned that some explosive snowman history is still being made today. Every year since 1818, the people of Zurich, Switzerland, celebrate the beginning of spring by blowing up a snowman. On the third Monday of April, the holiday Sechselauten is kicked off when a cotton snowman called the Boogg is stuffed with explosive and paraded through town by bakers and other tradesmen who throw bread to the crowds. The parade ends with the Boogg being placed on a 40-foot pile of firewood. After the bells of the Church of St. Peter have rung six times, representing the passing of winter, the pile is lit. When the snowman explodes, winter is considered officially over—the quicker it is burnt down, the longer summer is said to be.

    Gravity signals that race through the ground at the speed of light could help seismologists(地震学家) get a better handle on the size of large, destructive quakes soon after they hit，a study suggests. The tiny changes in Earth's gravitational field, created when the ground shifts, arrive at earthquake monitoring stations well before earthquake waves.

    “The good thing we can do with these signals is have quick information on the magnitude (震级) of the quake,” says Martin Vaillée, a seismologist at the Paris Institute of Earth Physics.

    Earthquake equipment in China and South Korea picked up gravity signals immediately after the magnitude-9. 1 Tohoku earthquake that destroyed parts of Japan in 2011. The signals appear as tiny accelerations on earthquake-recording equipment, more than a minute before the seismic waves show up.

    “We can look before the earthquake waves arrive,” says Vallée. “If we see nothing, we can say that the quake that made these was maybe large, but not huge. If we see the signals, it means we really have a very big quake. ”

    Had seismologists been monitoring for gravity changes, they might have realized sooner just how big the Tohoku earthquake was. A small increase in an earthquake's magnitude means a large change in the energy released by the quake-and the destruction expected. That information is important for emergency responders as they decide what resources to arrange.

    It'll be a major contribution if gravitational waves can beat down the time needed to know that a big earthquake is big. But much work remains before gravity signals can be considered a reliable tool in the vital minutes after a big quake. A few extra minutes of warning can save lives, particularly in coastal areas where people can flee ahead of an incoming tsunami.

    Some people believe that international sport creates goodwill between the nations and that if countries play games together they will learn to live together. Others say that the opposite is true: that international contests encourage false national pride and lead to misunderstanding and hatred. There is probably some truth in both arguments, but in recent years the Olympic Games have done little to support the view that sports encourage international brotherhood. Not only was there the incident of tragedy involving murder of athletes, but the Games were also ruined by lesser incidents caused principally by minor national contests.

    One country received its second-place medals with visible anger after the hockey final. There had been noisy scenes at the end of the hockey match, the losers objecting to the final decisions. They were convinced that one of their goals should not have been disallowed and that their opponents' victory was unfair. Their manager was in a rage when he said; "This isn't hockey. Hockey and the International Hockey Federation are finished." The president of the Federation said later that such behavior could result in the suspension of the team for at least three years.

    The American basketball team announced that they would not yield first place to Russia, after a disputable end to their contest. The game had ended in disorder. It was thought at first that the United States had won by a single point, but it was announced that there were three seconds still to play. A Russian player then threw the ball from one end of the court to the other, and another player popped it into the basket. It was the first time the US had ever lost an Olympic basketball match. An appeal jury（评审委员会）debated the matter for four and a half hours before announcing that the result would stand. The American players then voted not to receive the silver medals.

    Incidents of this kind will continue as long as sport is played competitively rather than for the love of the game. The suggestion that athletes should compete as individuals or in non-national teams, might be too much to hope for. But in present organization of Olympics there is far too much that encourages aggressive patriotism（爱国主义）.

    ⒈TrueCar.com

    Top dealers compete for your business by offering lower prices. TrueCar spends a lot of money and resources on making sure the entire car renting experience is simple and straightforward. If you're in the market for a new car, give this site a try first.

TrueCar's network checks many of the prices in your area and gets you the best price for the car you're looking for.

    ⒉Carvoy.com

    It offers more control by allowing you to “build your car” and select your rental plan. The “build your car” option is one of the better options for those looking to add on features to their car. If you're looking for cars with options like a sunroof or navigation (导航), it's Carvoy that makes it very easy to get started with the process.

    ⒊CarsDirect.com

    They have a large collection of new and used cars, and also provide resources for car comparisons. In the business for many years, they are one of the first online car outlets. They have a staff that can usually help you if you give them a call. Their phone support is very good and they are mostly located in the United States.

    ⒋CarRent.com

    It delivers your rental car to the door, which is actually a huge selling point. Many people don't like to go to a dealership or even drive somewhere to pick up a car. Imagine renting a car and having it delivered right to your doorstep, no driving necessary!

    ⒌CostcoAuto.com

    It offers member-only savings, many car selections and an easy sign-up process. The deals through Costco are great and unique. Many times they have deals with General Motors cars like Chevrolet. There are a lot of deals to be done, but the one thing that Costco does not do is negotiate the price.

    The Franklin Institute is one of the oldest and most beloved science museums in the United States.

    Why visit

    In 1824, the Franklin Institute opened in Independence Hall in memory of Benjamin Franklin and his scientific achievements. In 1934, with the construction of the current building and the nearby Eels Planetarium, it became a hands-on science museum.

    Today, it holds the distinction (荣誉) of being Pennsylvania's most visited museum. In the museum's rotunda (圆形厅), a 20 foot-tall marhle statue pays respect to the Founding Father and famous scientist.

    Must-See

    While the entire museum offers interactive (交互式的) fun, highlights include the high-tech Your Brain exhibits (展品), which offers a glimpse into the inner workings of the human brain; Sports Zone, which focuses on the scientific aspects of sports; Two Escape Rooms, where participants solve puzzles and riddles before lime runs out; and the on site Virtual Reality Demonstration Space.

    Pricing

    General Admission to the Franklin Institute includes access to three floors of hands-on science exhibits including permanent (永久的) interactive exhibits, Live Science programs, the Joel N. Bloom Observatory, and one show in the Fels Planetarium. Discounts are given for groups of 15 or more.

    To buy tickets, please click the ticket price to be directed to our online ticketing page where all the ticket prices are available. If you prefer to order tickets over the phone, please call 215-448 1200 (9: 00 a. m.—5: 00 p. m.)

    Member Tickets

    Members of the Franklin Institute receive exclusive (独有的) ticketing benefits, including discounted prices and no service fees. Please select your Membership level before buying member tickets.

In summer holiday, the kids are out of school, so it is a good time to plan for a family travel. However, it's not easy to prepare for a family travel. Here are four travel apps(应用程序) to make your trip more relaxing.

Yuggler

Search nearby for family-friendly activities, from free events to worthwhile attractions. Use Yuggler to plan for what to do each day, based on the weather or the type of entertainment your kids want or need, and look through reviews written by parents who've been there. So instead of paying $20 per person for entrance to the big museum, you can locate just-as-fun spots with zero admission, saving a family of $80.

Sit or Squat

Held by Charmin, this app uses your phone's built-in location finder to find out the closest public restrooms. Perhaps more importantly, Sit or Squat provides the restrooms'cleanliness scores, which are made by the users who have been there. It is quite convenient.

My Disney Experience

The official Walt Disney World app's interactive map(互动地图), which uses your tool's GPS, helps you find restaurants, restrooms, and attractions nearby. You can also access real-time wait times for popular rides and character appearances, meaning you're making the most of your time.

Wi-Fi Finder

Find free Internet near your current location in a minute. Wi-Fi Finder works offline too. Before you head out, download the offline database(数据库) to your phone, so you won't waste data while searching for a hotspot, which is key during an international trip. You'll save as much as $15 off the hotel Wi-Fi cost.