Pontoon bridge unprecedented 730-meter, fortified pontoon bridge across the Scheldt river at the Siege of Antwerp in 1584 to close off water access to the city. In the battle of Saraighat in 1671, the Ahoms spanned the river Brahmaputra at Saraighat over an improviso bridge of boats. In the 1670s, the French devised the copper pontoon; after this point, rivers and canals ceased to present significant obstacles. The early modern period in pontoon use was dominated by the wars of the 18th and 19th centuries during which the art and science of pontoon bridging barely changed. This however did not stop all
Junk silver European coins. 154 junk-copper U.S. pennies contain a full pound of .950 fine copper. Junk silver Junk silver is an informal term used in the United States, United Kingdom, Canada and Australia for any silver coin which is in fair or cull condition and has no numismatic or collectible value above the bullion value of the silver it contains. Such coins are popular among people seeking to invest in silver, particularly in small amounts. The word "junk" refers only to the value of the coins as collectibles and not to the actual condition of the coins; junk silver is not