Dreams of world peace are as old as wars. But as the women of Wales were recovering from World War I, they demanded peace in droves.

Still sorrowing the husbands, sons, and loved ones who fought in the war, in 1923 the Welsh League of Nations United (WLNU) drafted a petition (请愿书) at Aberystwyth University calling for a warless world.

The petition was signed by roughly three quarters of all the women in Wales and was said to be seven miles long. The document was then packed in a large oak chest and sent across the Atlantic.

It was the WLNU’s hope that America would join in their mission for peace, and so they toured with the petition across the country before President Calvin Coolidge gave it to the Smithsonian for preservation.

As the centennial anniversary of World War I approached, a plaque was found in the archives at the Temple of Peace in Cardiff mentioning the petition, but nobody knew what it was, says Mererid Hopwood, chair of the Women’s Peace Petition Partnership.

So in 2017, an email was sent to the Smithsonian inquiring about the status and location of the chest and its petition.

Having arrived at the National Library of Wales on March 29 this year, Hopwood received it along with other members of the Peace Petition Partnership and described opening the chest and finally getting to see its contents (内容) as an emotional moment.

Hopwood is hoping more Welsh citizens will have similar experiences now that the petition has returned to its original home. The petition will be digitized, along with all signatures and addresses, so the public can view it online and see if their grandmothers or previous tenants of their homes signed 100 years ago.

Clearly the world has not yet achieved the petition’s great goals, but Hopwood said the signatures gave her hope.

The Inca Empire was the most powerful of the day, ruling western South America between 1400 and 1533. And the Inca leaders sometimes needed vacations! That’s why the Inca built Machu Picchu in what’s now Peru. All that’s left today are ruins, but about 500 years ago, it was a bustling royal residence. Peek into the past to discover the secrets of this awesome spot.

The royal family lived mostly in the mountainous capital city, Cusco. But during the winter, they could move down to the warmer Machu Picchu. Emperor Pachacuti Inc a Yupanqui likely ordered construction of it around 1450. There, the royals could feast and entertain guests. The other 750 residents served the rulers and maintained the city.

Earthquakes are common in Peru, so Inca builders designed Machu Picchu to resist these shakes. They cut the stones to fit together, and they didn’t use any material, like cement, to bind them. This way, when the ground shook, the stones could bounce around and then settle back into place.

The Inca didn’t have a written language and instead used knotted cords called quipu (KEE-poo) to send messages and keep records. Experts think the style of the knot and the color of the string contained information. Researchers are now using computers to try to untangle these long-lost codes.

Along with silk and paper, gunpowder is another invention by Chinese and the Silk Road helped it spread to the West. The dating of gunpowder is as early as 850 AD. The Chinese used gunpowder to make fireworks and for signal flares (信号弹). Gunpowder was also thought to have been used in medicine and in alchemy (炼金术)．

This invention seems to have been discovered in China by accident — by alchemists when doing experiments.

The gunpowder used for military purpose was first recorded in 919 AD. By the 11th century，explosive bombs filled with gunpowder were introduced and used in China. The words “fire cannon (大炮)” “rocket” and “fireball” appeared time and again in the official Song history as well as two other books written during the same period.

The first detailed description of using the “fire cannon” in warfare was in connection with a battle fought in 1126 when the Song army used it against the invading enemy. The so­called “fire cannon” was a tube made of bamboo filled with gunpowder which, when fired, threw a flaming missile towards the enemy. According to a description of a battle scene in 1132, it took two persons to carry a “fire cannon”, and the cannons were fired from a moving platform. And this platform had to be moved close to the wall of the besieged (被围攻的) city.

The Chinese invention of gunpowder reached Japan，the Islamic countries and then Europe in the 13th century and the Arabs improved gunpowder for military use. The early account of gunpowder in Europe was recorded by English philosopher Roger Bacon in the 13th century.        

One century later the Arabs used it to attack the Spanish town Baza and the next year in 1326 Florence ordered the manufacturing of cannon and cannon balls. From Italy the making of gunpowder soon spread to other European countries, and by the 1350s it had become an effective weapon on the battlefield.