Treatise on Mathematical Instruments: Their Construction, Adjustment, Testing and Use Concisely ExplainedVirtue Bros. & Company, 1866 - 185 pages |
From inside the book
Results 1-5 of 46
Page 4
... round head , which rolls with ease between the fingers . The adjoining figures represent two varieties of bow pen , fig . 1 being well adapted to describe arcs of not more than one inch radius , and fig . 2 to describe arcs of small ...
... round head , which rolls with ease between the fingers . The adjoining figures represent two varieties of bow pen , fig . 1 being well adapted to describe arcs of not more than one inch radius , and fig . 2 to describe arcs of small ...
Page 33
... round three of its edges for readily setting off angles . In 150 90 12/0 1216 2/0 using this protractor , the fourth edge , which is quite plain , with the exception of a single stroke in the middle , is to be made to coincide with the ...
... round three of its edges for readily setting off angles . In 150 90 12/0 1216 2/0 using this protractor , the fourth edge , which is quite plain , with the exception of a single stroke in the middle , is to be made to coincide with the ...
Page 47
... round , by means of the milled head н , so that the graduated head BB makes one complete revolution , the vernier is advanced on the limb of the instrument , a distance B B equal to the difference of a division of the limb MICROMETER ...
... round , by means of the milled head н , so that the graduated head BB makes one complete revolution , the vernier is advanced on the limb of the instrument , a distance B B equal to the difference of a division of the limb MICROMETER ...
Page 50
... round a center at A. The two shorter rulers are connected in like manner with each other at F , and with the longer rulers at D and E , and , being equal in length to the portions AD and AE of the longer rulers , form with them an ...
... round a center at A. The two shorter rulers are connected in like manner with each other at F , and with the longer rulers at D and E , and , being equal in length to the portions AD and AE of the longer rulers , form with them an ...
Page 52
... round the instrument to the tracing point at c , enables the draughtsman at the tracing point to raise the pencil from the paper , whilst he passes the tracer from one part of the original to another , and thus to prevent false lines ...
... round the instrument to the tracing point at c , enables the draughtsman at the tracing point to raise the pencil from the paper , whilst he passes the tracer from one part of the original to another , and thus to prevent false lines ...
Common terms and phrases
accuracy achromatic adjustment altitude axis azimuth beam compasses bisected breadth bubble called chromatic dispersion clamp coincide colatitude compasses construction correct cross wires described diaphragm distinct vision Ditto ditto divided drawing edge equal error extent will reach eye-piece feet figure fixed focal length given number goniometer graduated half horizontal inches index glass instru instrument intersection IVY LANE latitude lens lenses limb line of collimation line of numbers line of sines logarithmic means measured ment meridian microscope number of degrees object-glass observed paper parallax perpendicular placed plane position primary divisions prism protractor quarter girt radius rays reading reflected image reflector refracting refracting telescopes represent right angles right ascension round secants sector sextant side Slide Rule sliding speculum spherical aberration spirit level square staff station subdivisions tangents telescope theodolite transit transverse distance triangle tube turning vernier scale vertical circle zero
Popular passages
Page 5 - To which is added, a description of the Principles and Practice of Isometrical Projection. By JF HEATHER, MA -With 14 Plates.
Page 69 - ... that the sine of the angle of refraction bears a constant ratio to the sine of the angle of incidence...
Page 98 - ... of this field of view. We must therefore place some fixed point in the field, of view, and in the focus of the eye-piece, and the point to which the measurement will have reference will be that point of the object viewed, which...
Page 6 - Gd. 131. READY-RECKONER FOR MILLERS, FARMERS, AND MERCHANTS, showing the Value of any Quantity of Corn, with the Approximate Values of Mill-stones & Mill Work.
Page 11 - THE ENTIRE SERIES IS FREELY ILLUSTRATED ON WOOD AND STONE WHERE REQUISITE. The Public are respectfully informed that the whole of the late MB.
Page 5 - Gd. 55. NAVIGATION ; the Sailor's Sea Book : How to Keep the Log and Work it off, &c. ; Law of Storms, and Explanation of Terms, by J. Greenwood. 2s.
Page 24 - From the center at a draw the line ag for the axis of the gnomon agi, and from g let fall the perpendicular gi upon the horizontal meridian line an, and there will be formed a triangle ag i.
Page 143 - ... of them, those which apply to the eye-end of the telescope will answer much better ; the former having their errors magnified by the power of the telescope, will, in proportion to this power, and those errors, be less distinct than the latter. " In taking distances, when the position does not vary from the vertical above thirty or forty degrees, the handles which are attached to the circle are generally most conveniently used ; but in those which incline more to the horizontal, that handle which...
Page 3 - Denison. 3s. 6d. 78. STEAM AND LOCOMOTION, on the Principle of connecting Science with Practice, by J. Sewell. 2s. 78*.