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. Scientific American Volume 78 Number 01 (January 1898) . he sounding boat withthe telescope of his transit. For the benefit of those of our readers who may notbe familiar with surveying instruments, we would saythat a transit is an instrument having a telescope soattached to a graduated circle that its exact amountof rotation around its pivot may be noted. Conse-quently, the angle formed by the position of the boat,the transit station and some fixed object on the shoremay be very accurately and quickly determined, evento the small fraction of a degree. In a circle there are 360 degrees, each
. Scientific American Volume 78 Number 01 (January 1898) . he sounding boat withthe telescope of his transit. For the benefit of those of our readers who may notbe familiar with surveying instruments, we would saythat a transit is an instrument having a telescope soattached to a graduated circle that its exact amountof rotation around its pivot may be noted. Conse-quently, the angle formed by the position of the boat,the transit station and some fixed object on the shoremay be very accurately and quickly determined, evento the small fraction of a degree. In a circle there are 360 degrees, each of which is sup-posed to be divided into 60 minutes, and each minuteinto as many seconds. Since a degree on the circleof the transit occupies a space of a pins head, itis, of course, impossible to subdivide each degree intominutes and seconds, but these small spaces are easilyread by an attachment called a vernier. To many per-sons it will seem too trifling to take notice of so smalla space as the minute of a degree, but that much of an THaHSiT tTATtm i. ? -4--:. -^^T-^ii-^^--:::• BANOE LINES AS BUN BY THE SOUNDING £OAT. ,\ui, is-y^jgrs-
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Keywords: ., bookcentury1800, bookdecade1890, booksubjectdevice, booksubjecttb