We do not know when man first began to use salt, but we do know that it has been used in many different ways throughout history. Historical evidence shows, for example, that people who lived over 3,000 years ago ate salted fish. Thousands of years ago in Egypt, salt was used to preserve (保存) the dead.

    Stealing salt was considered a major crime (罪行) during some periods of history. In the eighteenth century, for example, if a person was caught stealing salt, he could be put in prison and his ears could be cut off.

    In the Roman Empire, one of the most important roads was the one that carried salt from the salt mines to Rome. Guards were stationed(安置) along the route to protect against salt thieves, and they received their pay in salt, thus bringing the English word, salary. Any guard who fell asleep while on duty was thought to be “not worth his salt”, and as a result he would get a little less salt on his next payday. The expression, “not worth his salt”, is still used today in English.

    In the modern world salt has many uses beyond the dining table. It is used in making glass and airplane parts, in the growing of crops, and in the killing of weeds (杂草). It is also used to make water soft, to melt (融化) ice on roads and highways, to make soap, and to fix colors in cloth.

    Salt can be got in various ways besides being taken from mines underground. Salt water from the ocean, salt water lakes or small seas can be used to make salt. Yet, no matter where it comes from, salt will continue to play an important role in the lives of people everywhere.

    Do you want to live with a strong sense of peacefulness, happiness, goodness, and self-respect? The collection of happiness actions broadly categorized(把……归类) as “honor” help you create this life of good feelings.

    Here's an example to show how honorable actions create happiness.

    Say a store clerk fails to charge us for an item. If we keep silent, and profit from the clerk's mistake, we would drive home with a sense of sneaky (暗中的) excitement. Later we might tell our family or friends about our good fortune. On the other hand, if we tell the clerk about the uncharged item, the clerk would be grateful and thank us for our honesty. We would leave the store with a quiet sense of honor that we might never share with another soul.

    Then, what is it to do with our sense of happiness?

    In the first case, where we don't tell the clerk, a couple of things would happen. Deep down inside we would know ourselves as a type of thief. In the process, we would lose some peace of mind and self-respect. We would also demonstrate that we cannot be trusted, since we advertise our dishonor by telling our family and friends. We damage our own reputations by telling others. In contrast, bringing the error to the clerk's attention causes different things to happen. Immediately the clerk knows us to be honorable. Upon leaving the store, we feel honorable and our self-respect is increased. Whenever we take honorable actions we gain the deep internal rewards of goodness and a sense of nobility.

    There is a beautiful positive cycle that is created by living a life of honorable actions.

    Honorable thoughts lead to honorable actions. Honorable actions lead us to a happier existence. And it's easy to think and act honorably again when we're happy. While the positive cycle can be difficult to start, once it's started, it's easy to continue. Keeping on doing good deeds brings us peace of mind, which is important for our happiness.

    When Warren Buffett was asked about the secret to his wealth and success, he said that he read every day—500 pages. Unfortunately, if you're already working 9-5, you might not have the time to read at all, let alone an entire book a day. But what if you could get the benefits of reading without sacrificing all of your free time? You can! With the Blinkist app, you get the key learning from the best notification books in minutes, not hours or days. Our experts transform these books into quick, memorable, easy-to-understand insights. Start with the 3 most-read titles on self-improvement and see if you don't feel a little more satisfied already.

    ⒈Thirteen Things Mentally Strong People Don't Do by Amy Morin

    12min

    Read it on Blinklst

    You can't escape misfortune in life. But you can change how you respond it. Do you struggle to get over your failures? Or talk a lot about things out of your control? Getting over these obstacles can have a very great influence on your everyday life. Morin shares how her most successful therapy patients overcame these difficulties.

    ⒉How to Stop Worrying and Start Living by Dale Carnegie

    19min

    Read it on Blinklst

    How would you feel it someone told you on Sunday evening that, come Monday morning, you would be thrown into a torture chamber（刑讯室）? Would you worry? Probably. But there would be a way to deal with those worries. Ever wondered why you can't stop worrying about something? No matter how hard you try, are you always thinking and talking on the same issue? By defining the source of your stress, you can get over it once and for all. Carnegie came up with a timeless formula that helps you handle any overthinking situation.

    ⒊How Will You Measure Your Life? by Clayton M. Christensen, James Allworth and Karen Dillon

    13min

    Read it on Blinklst

    What do you think would make you happier at work? Perhaps a little more pay might be nice, or maybe some more admiration from fellow colleagues. Are you making the right trade-offs in life? While career achievements can be satisfying, neglecting your family and friends can be harmful in the long-run – in ways you can't even imagine.

    We are lucky to live in a world that is full of incredible technology. Our living rooms are packed with computers, LCD TVs, video game systems, and Blue-ray players that help us enjoy the latest entertainment. Although these items bring us joy and convenience, they also create a lot of junk. Each device needs its own plug and adaptor to keep its batteries recharged, and over time these wires get tangled (缠绕在一起的). Thankfully, something has come along to help rid our homes of this mess while still supplying these devices with the power they need. It's called wireless charging and this trend is just starting.

    Wireless charging has a lot of potential for smartphones and other electronic devices. Electronic devices can absorb the electricity once they're placed on a special charging mat. There are several advantages that wireless charging offers over traditional methods. For starters, cords (电线) have a tendency to wear out with use. Wireless charging users never have to worry about buying replacement cords. Wireless charging is also far more convenient for medical implants, as patients won't need to recharge their devices through the skin using cords. In turn, this cuts down on the risks of infection. Wireless charging can also bring safety benefits, as wired charging devices that come in contact with water can increase the chances of getting an electric shock. Wireless charging gets rid of that danger completely.

    Still, there are a few drawbacks to wireless charging. The first is speed. It takes a bit longer to charge devices wirelessly than it does if the device is plugged in. The process also requires more heat, so devices tend to get a bit hotter, which could create other safety issues. Also, since devices must be left on a special pad while charging, it is harder to operate them while they are powering up. This limitation may be gotten rid of in the future, as researchers are developing transmitters (发射器) that can charge several different devices in a room without the need to connect to a charging pad. Although wireless-charging technology may be far from perfect, it seems like a step in the right direction as we move towards a less-tangled future.

    People have grown taller over the last century, with South Korean women shooting up by more than 20cm on average, and Iranian men gaining 16.5cm. A global study looked at the average height of 18-year-olds in 200 countries between 1914 and 2014.

    The results show that while Swedes were the tallest people in the world in 1914, Dutch men have risen from 12th place to claim top spot with an average height of 182.5cm. Latvian women, meanwhile, rose from 28th place in 1914 to become the tallest in the world a century later, with an average height of 169.8cm.

    James Bentham, a co-author of the research from Imperial College, London, says the global trend is likely to be due to improvements in nutrition and healthcare. "An individual's genetics has a big influence on their height, but once you average over whole populations, genetics plays a less key role," he added.

    A little extra height brings a number of advantages, says Elio Riboli of Imperial College. "Being taller is associated with longer life expectancy," he said. "This is largely due to a lower risk of dying of cardiovascular(心血管的)disease among taller people."

    But while height has increased around the world, the trend in many African countries causes concern, says Riboli. While height increased in Uganda and Niger during the early 20th century, the trend has reversed in recent years, with height decreasing among 18-year-olds.

    "One reason for these decreases in height is the economic situation in the 1980s,"said Alexander Moradi of the University of Sussex. The nutritional and health crises that followed the policy of structural adjustment, he says, led to many children and teenagers failing to reach their full potential(潜力)in terms of height.

    Bentham believes the global trend of increasing height has important implications "How tall we are now is strongly influenced by the environment we grew up in," he said. "If we give children the best possible start in life now, they will be healthier and more productive for decades to come."

    Many people like traveling, but they cannot take their dogs wherever they go. Some people let their dogs stay alone at home while others ask someone else to take care of their pets. If you're leaving your beloved pet at home for a holiday, it can turn into a bad experience. Luckily, you don't have to worry about your dogs anymore because Rover can cover for you while you are on leave. Rover is the latest service to offer at home dog boarding. It's a good alternative (替代物) to boarding your dog at a dog boarding kennel (狗舍) or your neighbor's house.

    The way Rover works is sort of like Airbnb. Dog owners surf the Rover website or app for pet sitters (照看者), which can be organized by zip code (邮政编码) and available dates. Information of pet sitters is provided, complete with many reviews, specific services and rates. Now Rover has over 25,000 pet sitters in more than 5,000 US cities. And they're all experienced pet sitters.

    After finding someone that meets your needs, just send messages to the pet sitter to arrange a meeting. Then, like Rover says, all that is left to do is relax! Rover's pet sitters are encouraged to send text and picture information throughout the day, and if there's a medical emergency, the site will send a vet (兽医). Besides, don't worry about a pet sitter who fails to help you, because someone else will soon take his or her place.

    Happy doggie, happy travels—that sounds good to us. To learn more about Rover, click here.