Micrometer of from One- to Five-inch Capacity [Illustration: Fig.
Combined One- and Two-inch Micrometer] A combined one- and two-inch micrometeris shown in Fig.
For lengths of carriage travel greater than one inch, an end measuring rod, set to the number of even inches required, can be used between the micrometer point and lathe carriage.
The pin has freedom to move in a slot in the micrometer body, as shown in the enlarged view in the cut.
Micrometer Stop for the Lathe Most micrometer lathe stops are limited in their use to work where only a stationary height is required.
The bushing E is hardened and lapped, and fitted tightly in the forward counterbore of this sleeve, where it acts as a guide for the front end of the micrometer screw.
In order to overcome this difficulty and eliminate the personal equation in the manufacture of duplicate and interchangeable parts, the sensitive attachment to the micrometer shown in Fig.
Micrometer Caliper Square] The barrel is graduated in fifty divisions, each division equaling 0.
The sliding jaw C is made of tool steel, hardened, ground and lapped, and combined with it is the micrometernut which is drawn to a spring temper.
Sensitive Micrometer Attachment] The auxiliary barrel A is held to the anvil of the micrometer by means of a thumb screw B.
Adjustment is accomplished by means of either of two screws which makes micrometer adjustment possible.
This lateral movement is accomplished by means of the micrometer screw.
Two micrometer screws are provided for load adjustment--one for the full load and the other for the light load adjustment.
Means for varying the normal voltage which it is desired to maintain are provided in the spring attached to the balance beam and controlled by the micrometer adjusting screw.
Approximate appearance of the interference bands and micrometer wires as seen in the eye-piece of the telescope of the Ether machine.
Then we begin to spin the disks, and when they are going at some high speed, measured by a siren note and in other ways, the micrometer wires are reset and read--reset several times and read each time.
The method of observation now consists in setting a wire of the micrometer accurately in the centre of the middle band, while another wire is usually set on the first band to the left.
Then the micrometer heads are read, and the setting repeated once or twice to see how closely and dependably they can be set in the same position.
The slit and collimator are shown; the micrometer end of the observing telescope is out of the picture.
But before the phenomena had ceased I spared a few minutes from the somewhat mechanical work at the micrometer to take a view of the transit in the more picturesque form which the large field of the finder presented.
The method of observing which Brünnow employed was quite different from that of Struve, though the filar micrometer was used in both cases.
Venus by this time was well on the sun, and we therefore prepared to make observations with the micrometer attached to the eye-piece.
In the filar micrometer two spider lines are parallel, and one intersects them at right angles.
The objects to which the astronomer applies the micrometer are usually anything but small.
If not, the cross wire of B was moved till it coincided with dot 0, and the number of divisions of the micrometer head noted.
They watched Parrish as his eyes wandered along the rows of figures, while his fingers moved the micrometer screws.
The voice inside the Atom Smasher spoke again: "Turn all the micrometer screws until the needles register zero, Parrish.
A simple, fairly accurate, and easily made apparatus of the micrometer form may be constructed as shown by the accompanying sketch.
At the point N of the horizontal tube RN is the micrometer scale, illuminated by the mirror O.
Coarse adjustment by rack and pinion, fine adjustment by micrometer screw with graduated head.
This device may be so adjusted as to move the micrometer disc any number of teeth from one to ten with each sweep of the knife.
The objectclamp is raised vertically by a micrometer screw.
Glass slide with cell= 2/10 mm deep, with ocularmicrometer No.
The stand is inclinable and fitted with revolving centering stage, coarse adjustment by rack and pinion, fine adjustment by micrometer screw with scale.
Glass-Micrometer for the eye-piece=, to drop on the diaphragm of the eye-piece.
The fine adjustment= consists of a micrometer screw which moves the tube and arm of the microscope supporting the coarse adjustment vertically upon a triangular column.
A micrometer screw, in addition to the main valve of the CO{2} cylinder, is useful for governing the rate of flow.
So exact are they that a star can be brought from the edge of the field and stopped instantaneously behind the micrometer wire.
The worm-screw has a hand-wheel with a micrometer graduation into 250 divisions of its circumference.
The operation of both forms is identical except that the internal micrometer is placed inside of the bore to be measured while the external form is used just the same as a caliper.
The inch micrometer shown is set to five-tenths or five hundred one-thousandths or one-half inch.
With a metric micrometer there are fifty graduations on the barrel, these representing .
At Left, Special Form of Vernier Caliper for Measuring Gear Teeth; at Right, Micrometer for Accurate Internal Measurements.
The micrometer may be of the caliper form for measuring outside diameters or it may be of the form shown at Fig.
If the micrometer is rotated one full turn the opening between the spindle and anvil will be .
After a record has been made it is read by means of a micrometer microscope, the angle moved through by the photographic disk is found, and hence the time period between two events.
When very close readings are required, they are made by means of a traversing geometric micrometer microscope.
In this instrument the micrometer screw, with a divided circle for turning it, was applied for bringing the micrometer wire actually in line with a division on the circle--a plan which is still always adopted.
Huyghens used a metal strip of variable width in the focus, as a micrometer to cover a planetary disc, and so to measure the width covered by the planet.
The reflection of the micrometer wires and of a star very near the zenith (but not quite in the zenith) can be observed together.
An extension on the sleeve carries a micrometer screw brush adjustment.
This gives a regular micrometer means of varying the effective magnet strength.
By means of the micrometer slide in the stage and the micrometer eye-piece, the internal layer 0.
A microscope micrometer is focussed on a mark made on the plant-holder, and the amount of subsidence of the mark determined after one minute; this was found to be 0.
At the two ends of the frame the micrometer screws are afforded journal bearings.
But if they do not coincide, then the amount of error may be found by the micrometer wheel G, Fig.
If not, the cross-wire of B was moved till it coincided with the dot 0 and the number of divisions of micrometer head noted.
It was Huygens, together with Malvasia and Auzout, who first applied the micrometer to the telescope, although the inventor of the first micrometer was William Gascoigne, of Yorkshire, about 1636.
The principle of Gascoigne's micrometer was that of two pointers lying parallel, and in this position pointing to zero.
The micrometer as used in telescopes enables the observer to measure accurately small angular distances.
Huygens was one of the first to adapt the micrometer to the telescope--a mechanical device on which all the nice determination of minute distances depends.
Huygens's micrometer was a slip of metal of variable breadth inserted at the focus of the telescope.
Any mechanic knows that it is a sad waste of time and pains to standardize tenons, with micrometer and emery paper, to a thousandth of an inch, so long as the mortises are left unstandardized.
We cannot put a man on the scales and determine that he has so many milligrams of common sense, or apply the micrometer to him and say that he has so many millimetres of financial ability.
The measurement depends on the accuracy of the micrometer screw, which is cut and corrected with great care.
The micrometeron microscope as shown in cut is not furnished with instrument.
The micrometer is fitted with sliding eye piece and counter for full revolutions.
The top carriage can be moved by hand and accurately set by means of a micrometer screw.
In making measurements of exhibits, the Kew micrometer devised by Sir Joseph Hooker is of much service.
Before the invention of the micrometer exactitude was impossible, because the adjustment of the instrument depended on the discrimination of the naked eye.
The micrometer was a further advance in exact measurement.
The micrometer has thus measured the difference of the zenith distances, and the calculation to get the latitude is most simple.
The micrometer microscopes must also measure correct quantities on the divided circle or circles.
In this device there is a movablemicrometer wire which is brought by hand into coincidence with the star and moved along with it; at fixed points there are electrical contacts, which replace the fixed wires.
By repetition of this process, the reading of a micrometer indicating the end of each position of the bar, the measurement is made.
Two extremely sensitive levels are attached to the telescope, which latter carries a micrometer in its eye-piece, with a screw of long range for measuring differences of zenith distance.
These errors can nevertheless be almost entirely avoided by using the impersonal micrometer of Dr Repsold (Hamburg, 1889).
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "micrometer" in a variety of sentences. We hope that you will now be able to make sentences using this word.
