History of the bicycle fashion of the day made the "ordinary" bicycle inaccessible. Queen Victoria owned Starley's "Royal Salvo" tricycle, though there is no evidence she actually rode it. Although French and English inventors modified the velocipede into the high-wheel bicycle, the French were still recovering from the Franco-Prussian war, so English entrepreneurs put the high-wheeler on the English market, and the machine became very popular there, Coventry, Oxford, Birmingham and Manchester being the centers of the English bicycle industry (and of the arms or sewing machine industries, which had the necessary metalworking and engineering skills for bicycle manufacturing, as in Paris and St.
Mode of a linear field Mode of a linear field In physics, a vector field is linear if it is a solution of a set of linear equations "E". For instance, in physics, the electromagnetic field in vacuum, defined in the usual (3 + 1)-dimensional space "S", obeys Maxwell's equations. A linear combination of electromagnetic fields, with constant, real coefficients, is a new field which obeys Maxwell's equations. The solutions of the linear equations are represented in a real vector space "M". A radius of "M", which represents proportional solutions, is called a "mode". A norm may be defined. For instance, in electromagnetism, it is