St. Paul daily globe. [volume] (Saint Paul, Minn.) 1884-1896, 1895-01-13

A mass Of facts is slowly accumnlatlng
in which foundation like that OF some
great building is in process OF construc-
tiOn.
Prof. r. II. Thurston. director OF Sib--
ley college. Ithaca, n. Y, SO long ana
favorably known for the eXactness ana
care with which lie treats a sclentlhc
question, presented q paper at the aerial
navigation conference on Tine Ma.
terials of Aeronautical Engineering"
infinitely and accurately comparing the
tensile strength, as related to llghtness,
of cast iron, bronze, wrought iron, steel
and aluminium. He finds that silk is
the strongest known substance III pro-
portion to its weight, and that ITS Sus-
pended fiber should carry about 150,O00
feet of its own material" This is SIX
times as large figure as is lound 1of
aluminium and for steel OF 10000 POUNDS
tenacity, and 30 per cent greater thali Is
reported as obtainable with steel III the
form Of watch springs OF fine wire. This
is good Illustration OF the thorough
ness with which aerial science is being
worked out. The weight, strength, air
pressure, curve OF surface i'll aero
planes made of OF bound with steel,
silk, spruce, hemp and aluminium are TO
be known before any one ventures TO
set forth
- With a Flying Machine.
1t is remarkable that the present
progress in this science is not accom-
panied by many attempts at motor flight.
but by the accumulation of much need
ed knowledge of the laws of supporting
air pressure and the weight of material
determined by actual experiments, rein
forced by mathematical estimates.
Langley'S experiments indicate that
mathematical estimates as related to
square disks in motion can be extended
to include the known strength Of MAJ
terial as related to pressure upon curved
surfaces. These data. when all COM
pleted to certain needed point, will in
of controlled power as well as safety. In
other words, these fundamental esti
mates are gradually smoothing the way
for safe movements in the vast air
spaces above the Garth.
A brief review of the flying machines
actually constructed, as recorded by MIR.
Chanute in his historical researches
from 1869 forward, places before us u
long list Of machines that have failed TO
leave the ground, not less than seventy
two men having tried unsuccessful eX-
periments. These frutleSs efforts in
cIude rather dimly authenticated ac>
count of one in the fourteenth century,
Short flights since made with artificial
beating wings under the impulse of
twisted rubber (Which eXerts temper
arily great power in proportion to its
weight), with small models, have been
we'll authenticated. Motors worked by
steam and compressed air, or by the re-
coil of exploding cartridges, Oh too
small scale to carry human wight,
have also flown we'll enough to greatly
stimulate the activity of inventors. The
distances made from leastto greatest |
have arranged consecutiyely as follows:
A LeIpsic opticians machine few 3
feet in 1871; Sutton's, IL feet in 1888;
Bourne,s, 20 feet in 1885,, Degen's. 81
feet in 1912; CastePs, ~ feet i'll 1878;
Penaud's, 30 feet in 1871; Tatin'S, IS
feet in 1876; PiChancourt's, 20 feet in
1889; BaQueville's, 1870 feet in 1912;
Spencer's, 100 feet in 1865; Trouve's,
240 feet i'll 1891; Herrlng's, 800 feet in
1891; Hargrave's, of Austria, 100, $50,
270, 543, 3GS feet, with IS different ma
chimes from 1884 to 1898. Hargraye's
machines have shown better results.
partly because of improved material
and modern methods Of construction,
but mostly owing to the surprising in
genuity of the inventor.
AL of these short flights made by the
machines of various inventors seem to