The southern aegis, and Harford County intelligencer., 1863-09-18
Phenomena OF Camphor in Water.


scientific gossip! respecting the peculiari-
ties Of eampbar % water, is conc ensed
from the London Rl,QfographSe Ne,os: ID
When small piecssof camphor are drop
ped on thesurfacs OF a glass of water, scy.
eral curious pbenomena may be observed.
They Immediately commence to rotate,
and move about. withsremarks BILE energy
varying, sometimes iasIapidity, but usual
lyi conducting their gyrations in1a strange
and erratic manner. To order to. obtain
the best effects, some precautions are me-
cessary: thus, the oampbor should be
tolerably purea the piece employed should
be. cut and separated from the larger
lump with a,perfectly, clean instrument,
and contactlwith the fingers should be
1scrupulqusly ysayoided.r Moreover, the glass
should be,quite clean and the water pure.
When these conditions are satisfied, the
phenomena are really very striking, and
well ~ crit more attention than is,general-
ly devoted to such things. Several ply
sicians have observed thesei curions 1mO-
tions of acamphor; amongst, others may
be specially named, Mr.. Tomlinson and
Mr.. Lightfoot. The former gentleman
has been attracted more to the physical
phenomena involved in the movements,
whilst Mr. Lightfoot has principally stu!
died the chemistry of the subject Each
is Of interest, but it is TO some results re-
Gently found out in respect to the latter
branch of inquiry that we desire at presH
eut to draw attention. rr !s,seiig!-fu4
IF, insteadiof using torn or cut frag-
nent FROM lump Of camphor, one or two
line crystals are detached with 10 clean
needle point from the cork Of phial in
which camphor is kept, and these are let
fall on clean water,. they at once begin to
move about with wonderfully increased
rapidityg darting away in various direc-
tieus, as 1T shot from some miniature en-
gine, or endowed with life and will Of
their own each crystal quivering and
rocking ON the water with an apparent
high degree of indignation at its forced
contact with the humid surface. The fury
gradually diminishes and regular dance
begins; the various particles select part
ners, to some of5which they seem to cling
with pertinacity /; whilst Others will either
remain indifferent or, if attracted, will
only stay a. very short time in embrace,
and wander again in search of more con-.
genial. floating associates. lo u0.aio ods
!, The explanation which Mr.. Lightfoot
gives of these movements, is the emanas
tion Of q vapor from the volatile camphory
which has o very low tension; the water
upon whieh. it floats being capable of dis
solving and difusing the vapor more read
lily in certain directions of the crystalline
axes, thereby removes sufficient vapor
pressureiat those points, for the opposite
side to drive about (by recoif the nicely
suspendedIparticle. In certain Positions
two crystals of qeamphor will attract each
other, whilst in other situations there is
a IN utual repulsion. 1t will sometimes
happen that two crystals of .eamphor may
be- thrown on the water and net have any
tendencyqto locomotion. When this is
the case, a. continual trembling or vibra-
ton will be noticed ID the crystal. Whens
two such stationary vibrating crystals
come in contact by attraction, immediate-
Fly an eccentric, irregular change Of place
occurs, as if the force agitating each pre-.
vious to the grouping, produced a new re-
sultant force, in obedience to which the
fcombined crystals move. g3ae ssa pea
II In describing the method of separating
and placing the oamphor on1the water, we
laid some stress on the fact that every
thing should be quite clean, aud that the
!. fingers should not touchn the campher oins
[any stage. The reason Of this is obvious.
II, whilst camphor is actively moving bn
water,it the most minute particle tof certain
Egreasy substances touch the w1tef; in-
Issm taneously, as if BY some magic the
Ecampherli is deprived Of allmotioh. The
soehe Of, previous activity is changed ints
Iimmobiity. niThis curious property has
been mAde1iise Of by Nj. Lightfoot to de-
tect grease quantities SO extremely min.
ute, as would appear almost fabalous,A for
camphor cannot be made to, rotate on wa
ter, containing the utmost iin6aitesimal
portion Of ggease. Mr.. 4Ligktfoot has
: made usd of this test in . most ingenious
manner ITO distinguish between: the two
Idi6erenty methods of dyeiDg- cloth with
msdder and with hgarancine i II is difficulty
and often impossibIe for calico printers
! and merchants, 70 distinguish between the
! tmol; and as thee garahcine dye is more
: fugitive thansthb first, aud also Of less in
trinsic worthy it u sometimes substituted