. Sun dials and roses of yesterday; garden delights which are here displayed in every truth and are moreover regarded as emblems . co, 1877. The sec-ond is a Chinese dial with compass and this page is shown a circular silver box contain-ing a compass and dial. This is Japanese. There are many fanciful conceits for portabledials. The human hand is made into one by hold-ing it upright andthrusting a small stickbetween the thumb andforefinger, and turningthe loose end aboutuntil the shadow ofthis gnomon falls onthe line of life. Imake also an amusinglittle toy sun-dial,using as materia
. Sun dials and roses of yesterday; garden delights which are here displayed in every truth and are moreover regarded as emblems . co, 1877. The sec-ond is a Chinese dial with compass and this page is shown a circular silver box contain-ing a compass and dial. This is Japanese. There are many fanciful conceits for portabledials. The human hand is made into one by hold-ing it upright andthrusting a small stickbetween the thumb andforefinger, and turningthe loose end aboutuntil the shadow ofthis gnomon falls onthe line of life. Imake also an amusinglittle toy sun-dial,using as materials a plain glass cylinder-shapedtumbler, a knitting needle, and a slip of is a surprisingly accurate timekeeper. Some very fine and exact portable dials are manu-factured to-day. Flechets universal sun-dial, shownon page 159, is of great value to a traveller orexplorer. It will be seen by any student of dials tobe a general gnomonic form which has long beenmade, but in addition the curve of the mean time hasbeen traced upon the circle H in such a manner thatby an adjustment of the horary circle and an inclina-. Japanese Pocket-dial. Portable Sun-dials 159 tion of the axis, the latitude of the plane can bedetermined ; then of course the instrument can beadjusted to give the exact time of that place. A very interesting dial is sold in London whichwas devised by General Oliver, and the portable formis known by his name. It indicates mean time orclock time, which maydiffer from apparent timeas much as sixteen min-utes. This time-adjust-ment is accomplishedsimply by an enlarge-ment of a section of therod which is the gno-mon. Thus a curvedshadow is thrown in-stead of a straight meridional andequatorial arcs are ad-justable, and havescrews for fixing themat any given shadow of thisperfected gnomon fallson the equatorial circle. This dial and gnomon arean adaptation of the principle used in the cannon-dial shown on page 49. An ingenious card-dial da
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Keywords: ., bookcentury1900, bookdecade1900, booksubjectsundial, bookyear1902
