Edited sentence: ...That is, for example: fractions of an hour, if hour lines are drawn only for whole hours; or fractions of a half-hour if hour-lines are drawn for half-hours—etc....unless maybe the strings or wires are thick and clearly visible, or the sundial is used indoors by a window.Additionally, the wires or threads could present a hazard for birds landing in the sundial's vicinity.The Bifilar combines the building-ease, and the all-directional readability of the ordinary horizontal dial, with the uniformly-spaced hour-lines, and consequent easy inter-division estimation, of equatorial, equatorial-half-ring, and armillary sundials.The sundial is less simple than the ordinary horizontal dial.The uniform angular spacing of the hour-lines makes it possible to more accurately estimate fractions of a division.Though the uniform hour-line spacing seems a simplicity advantage, it is, arguably, outweighed by the fact that the demonstration of that property is more complicated than the demonstration of the construction of the ordinary horizontal sundial.Unless the wires or strings are thick, their intersection's shadow might not be as visible as that of a traditional gnomon