CHAPTER VIII.
REPRESENTATION OF FOUR-SPACE BY NAME. STUDY OF TESSARACTS.

We have now surveyed all the preliminary ground, and can study the masses of tessaracts without obscurity.

We require a scaffold or framework for this purpose, which in three dimensions will consist of eight cubic spaces or octants assembled round one point, as in two dimensions it consisted of four squares or quadrants round a point.

These eight octants lie between the three axes Z, X, Y, which intersect at the given point, and can be named according to their positions between the positive and negative directions of those axes. Thus the octant Z, X, Y, is that which is contained by the positive portions of all three axes; the octant Z, X, Y, that which is to the left of Z, X, Y, and between the positive parts of Z and Y and the negative of X. To illustrate this quite clearly, let us take the eight cubes—Urna, Moles, Plebs, Frenum, Uncus, Pallor, Bidens, Ostrum—and place them in the eight octants. Let them be placed round the point of intersection of the axes; Pallor Corvus, Plebs Ilex, etc., will be at that point. Their positions will then be:—

Urnain theOctantZXY
MolesZXY
PlebsZXY
FrenumZXY
UncusZXY
PallorZXY
BidensZXY
OstrumZXY

The names used for the cubes, as they are before us, are as follows:—

Third Block.
Third
Floor.
- Arcus MalaOvis MalaPortio Mala
Laurus MalaTigris MalaSegmen Mala
Axis MalaTroja MalaAries Mala
Second
Floor.
- Postis MalaClipeus MalaTabula Mala
Orcus MalaLacerta MalaTestudo Mala
Verbum MalaLuctus MalaAnguis Mala
First
Floor.
- Telum MalaNepos MalaAngusta Mala
Polus MalaPenates MalaVulcan Mala
Cervix MalaSecuris MalaVinculum Mala
Second Block.
Third
Floor.
- Ara MalaVomer MalaPluma Mala
Praeda MalaSacerdos MalaHydra Mala
Cortex MalaMica MalaFlagellum Mala
Second
Floor.
- Pilum MalaGlans MalaColus Mala
Ocrea MalaTessera MalaDomitor Mala
Cardo MalaCudo MalaMalleus Mala
First
Floor.
- Agmen MalaLacus MalaArvus Mala
Crates MalaCura MalaLimen Mala
Thyrsus MalaVitta MalaSceptrum Mala
First Block.
Third
Floor.
- Mars MalaMerces MalaTyro Mala
Spicula MalaMora MalaOliva Mala
Comes MalaTibicen MalaVestis Mala
Second
Floor.
- Ala MalaCortis MalaAer Mala
Uncus MalaPallor MalaTergum Mala
Ostrum MalaBidens MalaScena Mala
First
Floor.
- Sector MalaHama MalaRemus Mala
Frenum MalaPlebs MalaSypho Mala
Urna MalaMoles MalaSaltus Mala

Their colours can be found by reference to the Models 1, 9, 2, which correspond respectively to the First, Second, and Third Blocks. Thus, Urna Mala is Gold; Moles, Orange; Saltus, Fawn; Thyrsus, Stone; Cervix, Silver. The cubes whose colours are not shown in the Models, are Pallor Mala, Tessera Mala, and Lacerta Mala, which are equivalent to the interiors of the Model cubes, and are respectively Light-buff, Wooden, and Sage-green. These 81 cubes are the cubic sides and sections of the tessaracts of an 81 tessaractic Set, which measures three inches in every direction. We suppose it to pass through our space. Let us call the positive unknown direction Ana (i.e., +W) and the negative unknown direction Kata (-W). Then, as the whole tessaract moves Kata at the rate of an inch a minute, we see first the First Block of 27 cubes for one minute, then the Second, and lastly the Third, each lasting one minute.

Now, when the First Block stands in the normal position, the edges of the tessaract that run from the Corvus corner of Urna Mala, are: Arctos in Z, Cuspis in X, Dos in Y, Ops in W. Hence, we denote this position by the following symbol:—

ZXYW
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