The Practice of Engineering Field Work, Applied to Land, Hydrographic, and Hyraulic Surveying and Levelling, for Railways, Canals, Harbours, Towns' Water Supply ... Including the Description and Use of Surveying and Levelling Instruments and the Practical Application of Trigonometrical TablesAtchley, 1858 - 324 σελίδες |
Αναζήτηση στο βιβλίο
Αποτελέσματα 1 - 5 από τα 100.
Σελίδα 2
... inches , and these again into forty or fifty equal parts , horizontally and vertically , is very good practice ; so is describing a hundred circles in one of two inches diameter . When he can readily do this , he will handle his compass ...
... inches , and these again into forty or fifty equal parts , horizontally and vertically , is very good practice ; so is describing a hundred circles in one of two inches diameter . When he can readily do this , he will handle his compass ...
Σελίδα 3
... inch too long or too short , we shall have an error of 400 inches , or half a chain , and so in proportion as the line measures more or less ; hence the necessity for the length of the chain being correct . To make certain of this , a ...
... inch too long or too short , we shall have an error of 400 inches , or half a chain , and so in proportion as the line measures more or less ; hence the necessity for the length of the chain being correct . To make certain of this , a ...
Σελίδα 6
... inches off the right line , one way or the other , he will be generally many feet , perhaps yards , out of the true direction . When so far off , he will have to move many times backwards and forwards , as directed by the follower ...
... inches off the right line , one way or the other , he will be generally many feet , perhaps yards , out of the true direction . When so far off , he will have to move many times backwards and forwards , as directed by the follower ...
Σελίδα 7
... inch , it is another matter ; but of this we shall speak in another place . To return to our present subject , and further to illustrate our meaning , let the reader measure over three or four times a line of thirty or forty chains , at ...
... inch , it is another matter ; but of this we shall speak in another place . To return to our present subject , and further to illustrate our meaning , let the reader measure over three or four times a line of thirty or forty chains , at ...
Σελίδα 9
... brass rim enclosing the semicircle , is an opening of about a quarter of an inch in diameter , with a fine wire stretched horizontally across , coinciding with the diameter AB of the semicircle ; at the other end , which is the eye end ,
... brass rim enclosing the semicircle , is an opening of about a quarter of an inch in diameter , with a fine wire stretched horizontally across , coinciding with the diameter AB of the semicircle ; at the other end , which is the eye end ,
Συχνά εμφανιζόμενοι όροι και φράσεις
adjustment ascertain backsight base beam compasses bearing Bristol Channel centre chain line chainage channel chords circle clamp coefficient coincide column compass correct cosecant cosine coversine curve diameter difference of level direction distance ditto ditto divided Dumpy Level English Channel equal exterior angle fall feet fences field-book figures fixed gauge give given ground Gunter's chain half height Holyhead horizontal inches instrument intersection Irish Sea Length of Arc limb manner mark means miles minutes moon multiplied object observations obtain offsets overfall parallax parallel perpendicular plotted portion position practice protractor radius reading regard right angles rise scale secant sextant side sight sine square staff staff-holder station straight line stream subtended subtract surface survey tables taken tangent tangent screw tangential angle telescope theodolite tidal tion traverse triangle velocity vernier plate versine vertical zero دو
Δημοφιλή αποσπάσματα
Σελίδα 43 - IF a straight line touch a circle, and from the point of contact a straight line be drawn at right angles to the touching line, the centre of the circle shall be in that line.
Σελίδα 50 - If, at a point in a straight line, two other straight lines, upon the opposite sides of it, make the adjacent angles together equal to two right angles, these two straight lines shall be in one and the same straight line.
Σελίδα 50 - If a side of any triangle be produced, the exterior angle is equal to the two interior and opposite angles ; and the three interior angles of every triangle are equal to two right angles.
Σελίδα 45 - ... subtending the obtuse angle, is greater than the squares of the sides containing the obtuse angle, by twice the rectangle contained by the side upon which, when produced, the perpendicular falls, and the straight line intercepted without the triangle between the perpendicular and the obtuse angle. Let ABC be an obtuse-angled triangle, having the obtuse angle ACB, and from the point A let AD be drawn perpendicular to BC produced.
Σελίδα 44 - If a straight line be divided into any two parts, four times the rectangle contained by the whole line, and one of the parts, together with the square of the other part, is equal to the square of the straight line which is made up of the whole and that part.
Σελίδα 44 - If there be two straight lines, one of which is divided into any number of parts, the rectangle contained by the two straight lines is equal to the rectangles contained by the undivided line, and the several parts of the divided line.
Σελίδα 62 - But this is no derogation to their truth and certainty, no more than it is to the truth or certainty of the three angles of a triangle being equal to two right ones; because it is not so evident, as "the whole is bigger than a part;" nor so apt to be assented to at first hearing.
Σελίδα 169 - TO THEIR DIFFERENCE ; So IS THE TANGENT OF HALF THE SUM OF THE OPPOSITE ANGLES', To THE TANGENT OF HALF THEIR DIFFERENCE.
Σελίδα 50 - The angles which one straight line makes with another upon one side of it, are either two right angles, or are together equal to two right angles.
Σελίδα 45 - Therefore, in obtuse-angled triangles, &c. QED PROP. XIII. THEOREM. In every triangle, the square of the side subtending either of the acute angles is less than the squares of the sides containing that angle, by twice the rectangle contained by either of...