The Bossier banner. [volume] (Bellevue, Bossier Parish, La.) 1859-1952, 1878-08-29

The Rev. W. H. Dallinger lately de-
livered lecture at The Royal Institu-
ton, descriptive of the recent researches
of DR.. Drysdale and himself. The OBJ
ject of the lecture was mainly to explain
the method of research which had been
employed. The first essays of the opti-
clans to produce So high powers " were,
as might be expected, feeble. These
powers amplifed, but did not analyze;
hence it began to be questioned whether
Zone could see more really with high
power than with moderate one" And
this was true at the time. But it is not
so now. The optieian has risen to the
emergency, and provided us with pow
ers OF great magnifying capacity which
carry an equivalent capacity for an anal
ysis. They open up structure in won
derful way when rightly used. The lee
turer began by projecting upon the
screen the magnified image of q wasp's
sting-an object about the 1.20th of an
inch in natural size-and beside it was
placed piece of the point of cambria
sewing-needle of the same length, mag
nifed to the same extent. The details
of the sting were very delicate and re-
fined, but the minute needle point be-
came riyen and torn and blunt under the
powerful analysis of the lens, showing
what the lecturer meant by magnify
ing power;'' not mere enlargement,
but the bringing out of details infinitely
beyond us save through the well made
lens. This was further illustrated by
means of the delicate structure of the
OF, f,, I,a,- Nv lr-
delicate valve of the diatom known as
N. ahom6oides. With a magniication
of 600 diameters no structure of any
kind was visible; but by gradually using
1900, 1,800 and 2. 400 diameters, it was
made manifest how the ultimate struct-
ure of this organic atom displayed it,
self.
But this power of analysis was carried
still further by means of the minutest
known organic form, Bdcteginna ter
mo. The lecturer had, in connection
with DR.. Drysdale, discovered that the
movements of this marvellous minute
living thing were effected by pair OF
fine fibers or s. fagella.' These were
so delicate as to be invisible to every
thing but the most powerful and spec
tally constructed lenses and the most
delicate retinas. But since this discov.
cry, DIR. Koch, of Germany, had actu.
ally photographed the flagella of much
larger bacteria, such as Bacillus sabtilis
and expressed his conviction that the
whole group was fagellate Mr.. Dial
linger determined then to try to meas
ure the diameter OF this minute fageE
lam of B. tern,o that the real power O
magnification in our present tense.
might be tested. This was most diff
cult task, but 200 measurements Wer,
made with four different lenses, and ths
results were for the mean of the frs
so measurements 0.000004S920S; fo
the second 0000004S8673; for the third
0'000004SS024; for the fourth, 100000
4SS200, giving a mean value for tn
whole, expressed in vulgar fractions, 0
the 1-204700O of an inch as the diane
ter of the flagellum of B. teamao.
With such power of analysis it wa
manifest that immense results might b
expected from good use of the @ high
est powers. The proper method O
using them was next dwelt on, and the
the apparatus was described, by mean
of which drop of fluid containing an
organism that was being studied Nigh
be prevented from cooperating Will
under the scrutiny of the most powerfu
lenses, and for an indefinite length c
time. The Importance Of studying sue
organisms in this way by continuou
observation-was then plainly shown
some of the peculiar differences of d.
Bastian, as to the transmutation {
bacteria into monads, and monads int
amebm, etc., being explained by di
continuity of observation iScieastit
Anaertcd15.