There is a general tendency for both bands and rays to appear brightest at their lowest parts; arcs seldom appear as bright at their summits as nearer the horizon.
Regular arcs were selected in most cases, but the lowest height obtained was for a collection of rays forming a curtain which was actually situated between the two stations.
It is not unusual for arcs and bands to look as if pulses or waves of light were travelling along them; also the direction in which these pulses travel does not seem to be wholly arbitrary.
Combining the results from arcs and bands, Carlheim-Gyllenskold gives the "anomaly" of the auroral meridian at Jan Mayen as 5.
At the same time, arcs near the horizon often appeared wider than others near the zenith.
But clearly, whilst the arcs and bands, and to a lesser extent the patches, showed a marked preference for the magnetic meridian, the rays showed no such preference.
A 360th part of the circumference of a circle, which part is taken as the principal unit of measure for arcs and angles.
A figure in the form of a crescent, bounded by two intersecting arcs of circles.
More rarely, an oval composed of two arcsnot representing a glory; a solid oval, etc.
A screw cut on a solid whose sides are arcs of the periphery of a wheel into the teeth of which the screw is intended to work.
Next you are to produce from this limb two narrower tracts horizontally, and from these are to be described the circular arcs of the letter between the line a.
The two arcs will touch above, in front, and below, in the rear, the exterior curvatures of this same letter S.
These are followed by other forms, in which simple arcs take the place of straight lines.
The instrument may be used likewise, as we have seen, to draw arcs of circles of the diameter C I or of the radius A O = r, whose center o falls outside the paper.
If the three rulers were three arcs of a large circle of a sphere, the instrument might serve for drawing the meridians on such sphere.
Le Luc to St. Tropez by coach, across the Maure mountains 144 +Les Arcs to Draguignan+ by rail.
With that simple motion, her nipples traced twin heliotrope arcs across the gossamer screen of her blouse.
Then he watched their hands, which moved in sculptural arcs through a kind of sign language certain Indians in the crowd seemed to know.
In the western Pacific these sweeping arcs extend into the ocean, where the mountain ranges project upward from the bottom of the sea with only the crests showing above the waves to point out, in dotted outline, the position of the mountains.
By the form and connection of the arms A C and B D, these arcs move opposite ways: and since they are grooved obliquely as shewn in fig.
In short there are six spaces, either left or cut on the shaft, opposite the three arcs D C D.
With the compasses, using A and B as centers, and with a radius longer than one-half of AB strike the arcs CD and EF.
Connect up the points where the arcs intersect to B and D; this is the face of the inclined prism, and contains the true shape of rail.
The general form being apparently a quatrefoil composed of semicircles on the sides of a square, it will be found on examination that none of the arcs are semicircles, and none of the basic figures squares.
For the efficiency of arcs of various kinds, expressed by the mean hemispherical candle power per ampere and per watt expended in the arc, the following figures were given by L.
As noxious vapours are however given off, flame arcs can only be used out of doors.
But the flame arcs with impregnated carbons cannot be enclosed, so the consumption of carbon is greater, and the carbons themselves are more costly, and leave a greater ash on burning; hence more trimming is required.
A In the case of direct-current arcs formed with solid carbons, Edlund and other observers agree that the arc resistance R may be expressed by a simple straight line law, R = e + fL.
Electric arcs between metal surfaces differ greatly in colour according to the nature of the metal.
In the hand-regulated arcs the carbons are moved by a screw attachment as required, as in some forms of search-light lamp and lamps for optical lanterns.
It is obvious that the higher the lamps are placed, the more uniform is the street surface illumination, but the less its average value; thus two 10-ampere arcs placed on masts 20 ft.
This is advisable for arcsincluded in a globe, and absolutely necessary in the case of lighthouse lamps and lamps for optical purposes.
For continuous-current arcs a cored carbon is generally used as a positive, and a smaller solid carbon as a negative.
With the centres A and B and distance BG describe arcs GHK and N.
With the centres A and F and radius DF describe arcs intersecting at G.
Then with centres K and L and radius AB describe arcs intersecting at I.
Now from E and F describe with the same radius the intersecting arcsat G and draw F G.
Those arcs and changing curves of the branches as they neared were sketching lines of pure horror whose meaning he still could not understand, save that they deepened in dreadfulness as he neared.
But before that tremor could shiver up the branches to him the hum of the living dynamo which was closing round his body shrilled up arcs of pure intensity into a thundering silence.
He also gave approximate rectifications of circular arcs after the manner of Huygens; and, what is very notable, he made an ingenious and, according to J.
From these results the mensuration of any figure bounded by circular arcs and straight lines can be determined, e.
Describe the figures of teeth for the developed arcs as for a pair of spur-wheels; then wrap the developed arcs on the cones, so as to make them coincide with the pitch-circles, and trace the teeth on the conical surfaces.
If weights be suspended from various points of a hanging chain, the intervening portions will form arcs of equal catenaries, since the horizontal tension (wa) is the same for all.
In order that there may always be at least two pairs of teeth in action, each of those arcs should be equal to the pitch.
Since, however, as already stated, the tooth curves are as often struck by arcs of circles as by templates, the application of such arcsand their suitability may be discussed.
M, marking as many arcs as there are points of division on B C.
It demonstrates, however, the impropriety of calling coarsely pitched teeth that are found by arcs of circles "epicycloidal" teeth.
By continuing this process we mark the numerous short arcs shown upon B, and the crowns of these arcs give us the outline of the return cam.
But if the arcs for the tooth curves are to be marked by compasses, the location for the centres wherefrom to strike these arcs may be marked from the points of division as was shown in Fig.
The dottedarcs C D represent the arcs of receding contact and C is found longer than D, the angles of action being 66 deg.
Thus, in the figure the inner dottedarcs show the path of revolution of the cutter when it was in the small arbor, and the outer arc of the path in the large arbor.
Thus suppose the pinion to drive in the direction of the arrows and the thickened arcs A B will be the arcs of approach, A measuring longer than B.
But at the Ends of the Arcs they retain'd their Order unchanged.
To draw curves that are not formed of arcs or parts of circles, templates called curves are provided, examples of these forms being given in Figure 6.
The triangle is then used to divide the circle into the requisite number of divisions c for the slots, and arcs i, j, are then drawn for the lengths of the slots.
As a result, the width or distance between the arcs and line G is different in the two views.
To avoid this the centre line 1, Figure 134, is first marked, and the arcs for the steps are then marked as shown.
Similarly for the wheel C the outer end curves are marked on the arcs g, h, i, and those for the other end of the tooth are marked between the arcs l, m.
The depth of the thread may then be marked on the other side of the bolt by the arcs d and e, and the line 14.
As both lines fall within less than a division, we subdivide that division as by arcs a, b, which divide it into three equal divisions, of which the lines occupy one division.
At short intervals he would look out anxiously into the uproar, turning his small, watchful eyes searchingly up to the tops of the masts, which never ceased to describe great arcs in the air (starboard to port, port to starboard!
He observed the huge arcsthat the lights on the mast described.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "arcs" in a variety of sentences. We hope that you will now be able to make sentences using this word.
