The southern press. [volume] (Washington [D.C.]) 1850-1852, 1851-06-09


Two sqpilaa16Al &lS4klss esmAlnsl I'm
ousdrilatessI 4enre, wish Oh he aides ana ~
opposite angles eQsst. Another equils&sral ri.
angle added TO the rhomi us forms tsspezed:
also fouF-sided figure. with two of IL oppo.
cite sides PARALLEL, but not the other two. The
fourth triangle added to the trapezsid on one
side forms rhomboid, a fouy-sided iguss, with
its opposite sides or angles equal bul not eli
the sides or angles Ii the triangle IL ADDED to
another side Of the trapezoid, the result il an
other equiluteral Triangle Four euuilstersl
triangies, when combined into = rh0mboid or
another triangle, can b. folded into tstr>sdron.
the most simple Of the Eve regular solids"
enclosed, OF course, in four equiiateyai tri-
angles. The tetssedron. through The most Sim
ple-and because the most simple Of al hsurea
with length, breadth, and thickn s-h.s pro-
'pertss exreedin ly interesting and curious.
When made Of pastsboard. in considerable num-
bers, it can be combined into forms liter.i1v
numberleas and namelcss, illustrating the works
of nature and Of art.
six equilateral triangles, combined around
one point ns cent,e, form regular hexagon;
plane fiat surface, with six eausl sidss and
angles. This figure has very peculiar proprr-
ties, exhibited in thousands OF forms in ths
mechanism of creation, as it il in works of ART.
As two trianales combined form the rhombus.
three Of the latter figure, like six Of the forme
make hexsgon. The triangular hexsgon. as
formed of triangles, and the rhombic hexaeon.
rs formed of rhombuses, together are capable
of combinations uniting economy, strength, and
beauty, sufficient for the employment of whole
life, becoming more interesting, rich, and beau
tlfui at every step Of progress in the work. The
simplicity OF such combinations fits them ad-
mirably for young hands, in which they work
with an assiduity which never tres. because
producing forms constantly new and ipcrsas-
ingly beautiful.
Eight equIateral triangles, combined in sew
eral different forms, can be folded into an oc.
taedron, one Of the five regular solids This ia
the primary crystal of very many crytaine forms.
as exhibited in nature, and as formed by art
The alum crystal is a regular octaedron, as may
be shown by dissolving half a pound Of alum in
pint of water, heated till the whole is dissolv-
ed, and then suffered to stand perfectly still,
with some form Of wire or other material i'm
mersed, till the water cools, when the octaedral
crystals Of alum will appear in regular forms
and in great numbers. The tetaedron, just de-
scrbed, combined with the octaedron here mem
toned, may produce new and greatly varied
forms, illustrating mechanism, both Of divine and
human origin, of illimitabIe extension, and indie
scrbably beautiful. Twenty equilateral trianeIes
folded may form an icosaedron, one of the
FIVE regular solids
ExPERIMEnT.-The few short articles on gag
ricultural geology" recently given to the public,
by being widely copied in public journals, both
in this and other countries have been made very
extensively reading lessons in schools. If Che
same should be done with 'smechanism," now
in progress, and various other subjects Of practi-
cal science, newspapers would become school
books" and schools be constantly enlivened and
enriched by something new instructve,a and enter
tanning, and thus relieved from their present dull
monotony, which compels thousands Of the most
talented scholars to become the most incorriQible
truants, the first step to blouse Of Refuse" and
other prisons.