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
Acoustic suspension acoustic suspension, with a separate, sealed air-space, even if the woofer itself is not. One notable exception to this was the Sonus Faber Stradivari Homage which uses a ported enclosure for the midrange. The two most common types of speaker enclosure are acoustic suspension (sometimes called pneumatic suspension) and bass reflex, so they are worth comparing. In both cases, the tuning affects the lower end of the driver's response but above a certain frequency, the driver itself becomes the dominant factor and the size of the enclosure and ports (if any) become irrelevant. In general, acoustic suspension systems (driver +