# Spiral Slide Rule: Equivalent to a Straight Slide Rule 83 Feet 4 Inches Long, Or, a Circular Rule 13 Feet 3 Inches in Diameter

Spon, 1878 - 20 páginas

### Comentarios de la gente -Escribir un comentario

No encontramos ningún comentario en los lugares habituales.

### Pasajes populares

Página 12 - To this the indtx has to be added. The index of the logarithm of a number greater than unity is one less than the number of figures in the integral part of that number. Thus the index of 5432 is 3, of 543-2 is 2, of 54-32 is 1, and of 5-432 is 0. Multiply or divide the resulting number by the power or root, as shown above. Then place the cylinder so that it reads on the scales (n and m) the decimal part of the quotient. The power or root is then at the index (c). In the result the number of figures...
Página 4 - The rule consists of a cylinder (d) that can be moved up and down upon, and turned round, an axis (/), which is held by a handle (e).
Página 4 - Two other indices (c) and (a), whose distance apart is the axial length of the complete spiral, are fixed to the cylinder (g). This cylinder slides in (/) like a telescope tube, and thus enables the operator to place these indices in any required position relative to (d).
Página 4 - The rule consists of a cylinder that can be moved up and down upon, and turned round, an axis, which is held by a handle. Upon this cylinder is wound in a spiral a single logarithmic scale. Fixed to the handle is an index. Two other indices, whose distance apart is the axial length of the complete spiral, are fixed to the cylinder.
Página 4 - ... to the cylinder (g). This cylinder slides in (f) like a telescope tube, and thus enables the operator to place these indices in any required position relative to (d). Two stops (o) and...
Página 13 - ... the number of figures in the product is the algebraic sum of the number of figures in the multiplier and multiplicand, if it is not read upon the same index as the latter, but it is one less than that sum if read upon the same index. The use of the scales...
Página 13 - Now placing the cylinder so that it reads -08661 on scales (n and m) the index (c) reads 12207, and the required power is 1220700000, having 10 figures, as the integral part of the above quotient is 9.
Página 11 - When either of the movable indices is at ono number and the fixed index at another, and the cylinder is turned into any other position, though the numbers at the indices will be different, their ratio will remain constant.
Página 14 - OF DECIMAL FRACTIONS. Write them as vulgar fractions, and multiply numerator and denominator by ten or a power of ten, so that the denominator may have a complete root. Then take the required root of the numerator by the method given above, and of the denominator by inspection : ТЬш\/Ч = Л/Т = V«L = ^ 10 103 10 102 101 1010...
Página 3 - Instruments, writes in relation to the foot slide rule : " The solution in fact may be considered as obtained to within a two-hundredth part of the whole.