The dentil course of the pedimental cornice takes the form of a peculiar reeded H pattern which is repeated in much finer scale on the edge of the corona, the abacus of the capitals and its continuation across the lintel of the door.
Neither is the abacus hidden as in the campaniform capital, but stands out boldly, and displays the cartouche of the royal founder.
Each head supports a fluted cornice, on which stands a naos framed between two volutes, and crowned by a slender abacus (fig.
The echinos provides the requisite projection; the abacus upon it forms the second transition from the circular plan of the shaft to the rectangle of the entablature.
The abacus and parts of the mouldings beneath it still exist; the coronation was formed by two roundlets, separated by a scotia, the lower being considerably smaller in height and diameter than the upper.
The abacus plinth was retained as the transition from the circular drums of the shaft to the broader oblong of the lintel.
The most common form of the capitals was a peculiar conjunction of two spiral scrolls, similar to a doubled Ionic capital, with an echinos-like roundlet beneath and a stepped abacus above.
Upon the narrow abacus moulding rested the entablature, remarkable for the Oriental character of the details, and notably for reminiscences of primitive wooden construction, which are almost as evident in the Ionic as in the Doric style.
The curved and projecting moulding which supports theabacus in the Doric capital.
A square abacus plinth is the only medium between shaft and ceiling, the two columns of the vestibule lacking even this.
A scamillus thus creates the incision between the upper drum of the shaft and the necking of the Doric capital, and is also occasionally inserted between the top of the abacus and the soffit of the epistyle.
The abacus is the crowning member of the capital, as the capital is of the column.
A second variety, discovered in the Didymaion, had only one wreath of leaves, and no connection with the square abacus by corner spirals.
Now, then," he thought, and sat up to the cranny; for the rattle of the abacushad stopped.
By replacing these little counters by sand, strewn evenly all over its surface, the abacus was transformed into a slate for writing or geometrical lessons.
During the Middle Ages the abacus still flourished, and it has left a further mark on our language by giving its name to the Court of Exchequer, in which was a table divided into chequered squares like this simple school appliance.
Thus the Corinthian capital is beautiful, because it expands under the abacus just as Nature would have expanded it; and because it looks as if the leaves had one root, though that root is unseen.
The interior of St. Pierre, according to Whewell, "bears a great resemblance to Early English work, although the French square abacus is still to be found here.
The round abacusis noticeable in the arcades under the windows of the choir, giving quite an English look to this portion of the church.
The same simplicity characterises the choir, which has four bays and a chevet of five-round arches, with massive piers, and the abacus square and voluted at the angles.
The English type of capital, with roundabacus and vigorous foliation, reminds one of the cathedrals of Salisbury and Lincoln; and the tympanum with its sadly-mutilated figures is carried on a corbel table of great beauty.
We have hitherto considered the abacus as necessarily a separate stone from the bell: evidently, however, the strength of the capital will be undiminished if both are cut out of one block.
In this case the weight borne is supposed to increase as the abacus widens; the illustration would have been clearer if I had assumed the breadth of abacus to be constant, and that of the shaft to vary.
Therefore, the more slender the shaft, the greater may be the proportional excess of the abacus over its diameter.
On this exquisite capital there is imposed an abacus of the profile with which we began our investigation long ago, the profile a of Fig.
The smaller the scale of the building, the greater may be the excess of the abacus over the diameter of the shaft.
Now the entire treatment of the capital depends simply on the manner in which this bell-stone is prepared for fitting the shaft below and the abacus above.
We assume, in B, that the width of abacus e f is twice as great as that of the shaft, b c, and on these conditions we assume the capital to be safe.
There one poor abacus stretched itself out to do all the work: here there are idle abaci getting up into corners and doing none.
The use of theabacus is eminently to equalise the pressure over the surface of the bell, so that the weight may not by any accident be directed exclusively upon its edges.
This abacus is formed by the cornice already given, a, of Plate XVI.
They are the exact contrary of the rude early abacus at Milan, given in Plate XVII.
The abacus superimposed might be on a very thin, little more than formal, as at b; but on c must be thick, as at d.
And lastly, Law 4 asserts the necessity of the thick abacus for the shallow bell; but the steep bell may have a thick abacus also.
The use of the circular abacus begun in the preceding century entirely supersedes the square abacus which was retained in France.
The next adding and calculating machine was an evolution from the digits of the human hand and is known as the abacus in China, and the soroban in Japan.
The abacus may be defined as an arrangement of movable beads which slip along fixed rods, indicating by their arrangement some definite numerical quantity.
Footnote: For some reason or other the particular capital shown in our illustration was not used in the building, but it is of the same model as those actually used, except that the edge of the abacus is not finished.
Treatises on the Abacus usually consist of chapters on Numeration explaining the notation, and on the rules for Multiplication and Division.
This instrument is in all essentials the same as the Swanpan or Abacus in use throughout the Far East.
Very few treatises on the use of the Abacus can be certainly ascribed to the eleventh century, but from the beginning of the twelfth century their numbers increase rapidly, to judge by those that have been preserved.
Geometria gives us a figure of an abacus of the second class with a set of counters arranged within it.
His treatise on the use of the Abacus was written (c.
Adelard of Bath, who also wrote on the Abacus and translated with a commentary Euclid from the Arabic.
Algorism quickly ousted the Abacus methods for all intricate calculations, being simpler and more easily checked: in fact, the astronomical revival of the twelfth and thirteenth centuries would have been impossible without its aid.
One leading characteristic of advance at Lincoln is the circular abacus of the columns, which is found throughout.
The abacus is plain, and the broad pilasters which carry the outermost order are beautifully carved on the broader face with a small running pattern of leaves.
This with the drip-mould springs from a billet-moulded abacus resting on broad square piers.
As in the older cloisters one long abacus unites the two capitals, but the arches are different, each being moulded as one deep arch instead of two similar arches set side by side.
They have no abacus proper, but instead two branches are bent round, bound together by a wide ribbon.
First each capital has a square abacus of some depth, then comes a large flat circle, one for each three caps, and at the top a star-shaped moulding of hollow curves, the points projecting beyond the middle of the square abaci below.
The thin columns are also round, but the bases are eight-sided; so are the capitals, but with a round abacus of boughs and twisted ribbons.
The abacus of each column is set diagonally to the diameter of the octagon, and between it and the lower side of the architrave are interposed thin blocks of stone rounded at the ends.
The Ravenna stilt and the Byzantine double capital were both of them shifts to relieve, as it were, the lightabacus of the Corinthian capital from the weight which the arch laid upon it.
The heavyabacus of Pisa and Lucca was a better escape from this difficulty.
The abacus has a width equivalent to the thickness of the bottom of a column.
The projection of the echinus beyond the fillet of the abacus should be equal to the size of the eye.
The height of the capital is to be such that, of the nine and a half parts, three parts are below the level of the astragal at the top of the shaft, and the rest, omitting the abacus and the channel, belongs to its echinus.
Let the height of the capital be divided into three parts, of which one will form the abacus with its cymatium, the second the echinus with its annulets, and the third the necking.
The height of the abacus is one seventh of the height of the capital.
The faces of the volutes must recede from the edge of the abacus inwards by one and a half eighteenths of that same amount.
Then, in describing the quadrants, let the size of each be successively less, by half the diameter of the eye, than that which begins under the abacus, and proceed from the eye until that same quadrant under the abacus is reached.
Let the breadth of the abacus be proportioned so that diagonals drawn from one corner of it to the other shall be twice the height of the capitals, which will give the proper breadth to each face of the abacus.
In the Ionic order the flat abacus of the Doric capital is replaced by two coiled volutes projecting beyond the echinus on either side, and the horizontal portion between the volutes is surmounted by finely carved leaf mouldings.
If they had been using an abacus constructed like the Russian chotü, and had placed this before all learners of the positional system, there would have been little trouble.
The operations of addition, subtraction, and multiplication upon this form of the abacus required little explanation, although they were rather extensively treated, especially the multiplication of different orders of numbers.
The words cifra and algorismus cifra were used with a somewhat derisive significance, indicative of absolute uselessness, as indeed the zero is useless on anabacus in which the value of any unit is given by the column which it occupies.
So the abacus held the field for a long time, even against the new algorism employing the new numerals.
Some of the abacus forms[557] previously given are doubtless also of the tenth century.
These Gerbert had marked on a thousand jetons or counters,[466] using the latter on an abacus which he had a sign-maker prepare for him.
It is possible that one of the forms of ancient abacus suggested to some Hindu astronomer or mathematician the use of a symbol to stand for the vacant line when the counters were removed.
The horns of the abacus of the capital have to project beyond the greatest width of the bell 2/7, i.
The persistence of this square abacus helps to call our attention to the continual changes undergone by the shaft which it surmounts.
It will be observed that in this case the abacus does not extend beyond the architrave, as it does in the Doric order of the Greeks.
The abacus then represents the rigid column behind the decoration, raising its summit above the drooping heads of lotus and papyrus, and visibly doing its duty as a support.
Finally, the square die or abacus which supports the architrave is much higher and more important than in the columns hitherto described, and it bears a mask of Hathor surmounted by a naos upon each of its four sides.
Between this quasi-capital and the architrave a low abacus is introduced (Fig.
Whenever the dimensions of the column were sufficiently great the stone beams which met upon the die or abacus had oblique joints.
At Karnak and Medinet-Abou this abacus is not so absurdly high as it afterwards became in the Ptolemaic period,[107] but yet its effect is singular rather than pleasant.
We mean the cube of stone which is interposed as a kind of abacus between the capital and the architrave.
The horizontal section of the capital is similar to that of the shaft, from which it seems to burst; it then gradually tapers to the top, where it meets the usual quadrangular abacus (Fig.
A cubic abacus or die of stone stands upon the circular surface of the capital and transmits the resisting power of the column to the architrave.
The slight inclination of the sides gives to the latter the effect of a cone, and the contrast between its almost circular top and the right-angles of the abacus helps us to remember that the square pier was its immediate progenitor.
A later variety of this type is found in a pillar in which the vertical band is interrupted to make room for a mask of Hathor, which is placed immediately below the abacus (Fig.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "abacus" in a variety of sentences. We hope that you will now be able to make sentences using this word. Other words: calculator; frieze; topping
