On the practical side, Torres built a whole series of analogue calculating machines, all mechanical. These machines used certain elements known as arithmophores which consisted of a moving part and an index that made it possible to read the quantity according to the position shown thereon. The aforesaid moving part was a graduated disk or a drum turning on an axis. The angular movements were proportional to the logarithms of the magnitudes to be represented. Using a number of such elements, Torres developed a machine that could solve algebraic equations, even one with eight terms, finding the roots, including the complex ones, with a precision down to thousandths. One part of this machine, called an "endless spindle" ("fusee sans fin") and consisting of great mechanical complexity, allowed the mechanical expression of the relation y=log(10^x+1), with the aim of extracting the logarithm of a sum as a sum of logarithms, the same technique which is the basis of the modern electronic Logarithmic Number System. Since an analogical machine was being used, the variable could be of any value (not only discrete prefixed values). With a polynomial equation, the wheels representing the unknown spin round, and the result gives the values of the sum of the variables. When this sum coincides with the value of the second member, the wheel of the unknown shows a root.