US99A - Compasses quadrant and protractor - Google Patents

Description

1 from one rule to the other when using the.

STATES PATENT OFFICE;

rumors wan-man on s'm'mnnsvitnn, VIRGINIA. comassns, comm, arm 1=12.0creatures.

Specification of Letters Patent li'o. dated December 6, 1886;

To all whom it may concern:

Be-it known that I FRANCIS Wmmmr,

The quadrant has the agrees marked on it' from 0 to ninety, and by opening the rules which are fastened at the center a screw, the back pointer will mark the agrees on the quadrant There is along, square, or oblong box which is fastened to either of the rules by a screw con val needle which'may berea ily' changed instrument as a compass; in running the southwest or northeast courses the box containin the magnetical needle must be on the leit hand rule, or that attached to the quadrant, and in running the southeast and northwest courses-the compass box must-be on the other rule. Now by setting the back pointer to the course called for, and move the instrument till the needles settle north and south on have your course. The staff used is such as is generally used by surveyors, with the exception that there is a notch in the socket so that the ball may be turned down at right angles from the perpendicular so that the compass will be changed to a' quadrant. The lower rulebeing leveled by the plumb or spirit-level, and by elevatmg, or depressing the upper scale until it V Engineering, &c., and do a magnetie tion till degrees of elevation, or depressibii. .-.There are two sets ofsi hts, one 'seton each rule. The method of using the said instrument to" ard against local attraction is thus perormed; run. the course with the ma without using the magnetic ting theinstrument to the angle call an one set of sights to rangewith the line you have ;run-;"t-he' other set will cut the object the quadrant will-mark the p netical needle, and if nolocal attractions F 'found on that line the-serve ma "be-made al ne egg-setfor,

mark the course ofthe other line which you mustrun by beck, andfor'esi hts so govern I t e'linelprecedinstrumentmaybe used-as apromanner: Set the the'line you have to by mg it till the whole survey is-completed The same tractor in the followi' back pointer to the sing a called for, andlay I one rule to the meridian line, and slide that rule up, or down the meridian line till you cut your last station,

course and so ]proceed from station to your p t is completed. I claim as my invention-'- 1.1,- The manner of constructing this instr'u ment with double sights upon two rules, or

scales as herein described, furnished, with a box containing a compassneedle constructs;

adaptedthereby to' ed in the manner, and the purposes herein set forth, and I also claim the manner of arranging thesocket, and ball'as to allow the used'cs a quadrant.

Test I Assam; Ham), J aims Tums.

instrument to be co and you have your 1 i mane-[s HITELEYQ