Double Malay kites or two tetrahedral kites, fastened together, tandem fashion, will be found stable, especially if the rear one be slightly smaller than the forward one.
The tetrahedral kite] The tetrahedral form invented by Dr.
In the triangular box and tetrahedral kites this bowing back is not so necessary, because the dihedral angle is provided in the construction.
This forms a single cell, and the large sizes are broken up into many small tetrahedral cells.
The tetrahedral form toward which the earth is tending 12 4.
The Tetrahedral Earth and Zone of the Intercontinental Seas, Bull.
In our study of the figure of the earth (Chapter II) it was found that these shields represent the truncated angles of the rounded tetrahedral form toward which the planet is tending (Fig.
The manner in which continent and ocean are dovetailed into each other in an east-and-west direction has been generally adduced as additional evidence for the tetrahedral figure as above described.
If we inquire why the earth in cooling should tend to approach the tetrahedral figure, an answer is easily found.
Thus the arc measured in an east-and-west direction across Europe revealed a different curvature near the angle of the tetrahedralfigure from what was found farther to the eastward.
The mediterranean seas of both the eastern and the western hemispheres likewise interfere with the perfection of the tetrahedral figure and require an explanation.
Other confirmations of the tetrahedral figure of the earth have been derived from a comparison of astronomical data, which assume the earth to be a perfect spheroid, with geodetic measurements, which are based upon direct measurements.
It is chiefly remarkable for its finely preserved fortifications constructed of tetrahedral and polygonal blocks of local limestone well jointed, with maximum dimensions of about 3 by 1 1/2 ft.
We come now to the second great tetrahedral group, which though very much complicated, is yet, for the most part, a repetition of familiar forms.
E 8 is a tetrahedral arrangement of duads on the meta level, set free as duads on the hyper.
The spores are obscurely tetrahedral and trivittate, as in the other species of the genus.
The spores are spheroid-tetrahedral and obscurely trivittate.
Not only does each have the typical triangular form which would naturally arise from tetrahedral shrinking of the globe, but there are four other cardinal points of resemblance.
Their movements were helped by the fact that the tetrahedral form of the earth causes almost all the continents to be united by bridges of land.
Even there, however, it is not wholly lost, for it revives in the cold, lofty continent of Antarctica, where it coalesces once more with the other great tetrahedral ridges of Africa and Australia.
Today, no less than in the past, the tetrahedral form of the earth and the relation of the tetrahedron to the poles and to the equator preserve the conditions that favor rapid evolution.
The tetrahedral or Reye complex is the simplest and best known of proper quadratic complexes.
The detailed study of each variety of complex opens up a vast subject; we only mention two special cases, the harmonic complex and the tetrahedral complex.
The general form is the Tetrahedral pentagonal dodecahedron (fig.
