War of the Quadruple Alliance the Triple Alliance, which became the Quadruple Alliance for which the war is named. Meanwhile, in July 1718 the Spanish, this time with 30,000 men again led by the Marquess of Lede, had also invaded Sicily, which had been awarded to the Duke of Savoy. They took Palermo on 7 July and then divided their army in two. De Lede followed the coast to besiege Messina between 18 July and 30 September, while the Duke of Montemar conquered the rest of the island. The French, Austrians, and British now demanded Spanish withdrawal from Sicily and Sardinia. The attitude of Victor
Quadruple-precision floating-point format implement nearly quadruple precision using "pairs" of double-precision values is sometimes called double-double arithmetic. Using pairs of IEEE double-precision values with 53-bit significands, double-double arithmetic can represent operations with at least a 2×53=106-bit significand (actually 107 bits except for some of the largest values, due to the limited exponent range), only slightly less precise than the 113-bit significand of IEEE binary128 quadruple precision. The range of a double-double remains essentially the same as the double-precision format because the exponent has still 11 bits, significantly lower than the 15-bit exponent of IEEE quadruple precision (a range of for double-double versus for