St. Paul daily globe., 1895-12-15

posite halves. Each half or side will
! have eight teeth, as now, but the teeth
will be cut on a new plan. There is a
! little hollow between each pair of
teeth, which will engage the links of
| the chain as it rolls along over the
| sprocket. The angle at which these
! little holloWs or grooves are cut has
been criticised. Bicycle scientists who
| claim to know say that the result will
| be an uneven, bumpety-bump motion
| on the part of the chain, together with
a rafting that will shock all ears at
| tuned, as it were, to the noiseless
rhythm of the perfect machine. No
self-respecting cyclist will ride wheel
that rattles.
However, the Simpson party say that
there is nothing in this criticism. Time
alone will tell. The little grooves are
supposed to be so many leverage
/ points, at each of which the link of
the chain will brace itself for the next
leap over the sprocket teeth. This
sounds plausible enough. Anything
that will help along the driving pro-
cess by ever so little is a welcome help
| to the wheelman. The little grooves
will thus act as conservators of en-
ergy. They will prevent the loss of
power. If they can do that they will
! be a great boon to the hill-climber.
! They will stop his hearts humping
against his ribs and save his wind.
THE SPROCKET IS LARGER.
But the most important feature Of
! this new sprocket is it's size. The
actual size of it appears in the illustra-
ton, drawn for the Sunday World from
the only specimen in this country.
At a glance it will be seen that it is
nearly twice the size of the ordinary
sprocket. But it has no more teeth
/ The latter fact is highly important. If
there were more teeth than on the or
binary Sprocket the gear of the wheel
would be 5O.4, assuming that the for
ward sprocket had the usual number
of eighteen. The average wheel is
! gcared to 63. A gear Of 5O.4 would be
an anomaly.
| The increased size of this new sprok-
ct, therefore, is the keynote of the
! Simpson invention. 1t permits the
chain to revolve about a larger radius
thereby increasing the driving power
of the chain. 1t does this with the eX-
ercise of no more power on the pedals;
in fact with the same power on the
pedals as is now eXerted by the aver
age rider, he can, with the Simpson
device, so it is claimed, drive his ma
chine harder and faster, the chain and
sprocket revolving the wheels with a
greatly increased force. which may be
multiplied in direct proportion to the
strength and skill of the rider, since
power and speed are interchangeable.
This large sprocket will really give
the bicycle higher gear, but without
calling for more driving power. 1t is
claimed that it will give the equivalent
of a gear of thirty-four on the ordinary
bicycle. A gentleman who has seen the
Simpson chain on an English machine
in England, says that some wheels with
this chain have had the equivalent of
a gear Of ninety-siX.
Since there are two halves to the
sprocket, each of whose eight teeth is
gripped by the link pins of the chain
in it's flight, there is a double forward
pull and double saving Of power, al
though by this is not meant that the
pull and saving are two-fold.
TRIANGULAR LINKS IN THE
CHAIN.
Then the chain itself is different from
the chains that now give such wonder
full service. The mathematics of this
chain are too deep for a newspaper
edited on popular lines. A Sunday
World reporter had these mathemati-
cal fine points of the Simpson chain re-
hearsed to him by an expert. 1t would
take a college professor with half a
dozen diagrams to explain them. Even
then it would all be as Greek to the
average bicyclist.
The links are triangular in shape, land
they are so Joined, it is claimed, that
they will afford a greater leverage on
the sprocket, and this leverage is con-
slant and regular through every revo-
luton.
The bicycle mathematicians in Eng
land have been busy, many of them
trying to prove that Mr.. Simpson-who
is, by the way, canny Scotchman-is
all at sea in his calculations. At the same
time not few of the practical me.
chanics over there have come to his
defense. There is very pretty quarrel
going on. This is apt to be the case
nowadays when any bicycle improve
ment is brought forward. The cranks