the clumsy blows of an antagonist, had overthrown them.  Assailant and assailed were in equilibrio, and personal equilibrium could not be restored.  Some such inane result may be witnessed when a pair of hostile iron-clads, out of sight of their nursing convoys, shall meet alone upon the deep; with the disagreeable difference that they will, if they go down, have a great deal farther to fall than the cuirassiers of the land.

[Illustration:  VIENNA EXPOSITION BUILDING AND GROUNDS, 1873.]

Since 1851 a new commercial cement had come into operation in the adoption by neighboring powers of the French metrical system.  England and America still hold out against the metre and the gramme; and the press of both occasionally levels at it the old jokes of making the spheres weigh a pound of butter and the polar axis measure a yard of calico.  With the innovation, however, our merchants have become perforce familiar, a large share of their imported commodities being invoiced in accordance with it.  Its immense superiority to our complicated and arbitrary weights and measures, in the tables whereof the same word often has half a dozen meanings, is beyond argument.  In the United States it has earned a quasi-official adoption, but the force of habit among the people has yet to be overcome.

We may here give, in evidence of the increasing hold these expositions have upon the popular mind, the gradual multiplication of the numbers exhibiting.  At London, in ’51, the exhibitors were 13,937; at Paris, ’55, 23,954; at London, ’62, 28,653; and at Paris, ’67, 50,226.

Austria, with admirable spirit, determined to anticipate her turn to enter the lists of peace.  Undismayed by Solferino and Sadowa, she had found her Antaeus in Andrassy.  Her capital city was advancing with immense strides in beauty and extent.  Geographically and ethnically it was, like the empire itself, a meeting-ground of north and south, east and west.  Isolated from the sea, it offered for the transport of heavy articles a system of railways proved by the event to be sufficiently effective.  It was decided that the march of progress should be more than kept up, and that the building, with its appendages, should be an improvement on all its predecessors in extent, in architectural effect and in solidity of material.  The dimensions are so variously stated, owing largely to difference of opinion as to what should be embraced within the admeasurement, that we are at a loss how to give them.  To the main building, however, was assigned a capacity of seventy-three thousand five hundred and ninety-three square metres.  Sixty-three hundred and eighty of these were awarded to France, ten metres less to England; and thirteen hundred and sixty to the United States.  The marquee-like rotunda rose to a height of two hundred and fifty feet, with a diameter at base of three hundred and fifty-four.  The principal entrance, with piers and arches of cut stone profusely decorated with statues and reliefs, was in highly satisfactory contrast to the fragile shells of glass and cast iron that sheltered the earlier exhibitions.