The Hawaiian gazette. [volume] (Honolulu [Oahu, Hawaii]) 1865-1918, 1878-04-17
Letter from DIR. TIsdale.
THE HEART.

To the Editor of the Haioaiian Gazette:
The heart is a muscular organ, suspended at itsup-
per extremity in the cavity of the thorax and swing
ing with every contraction of its venrices lit is not
in size, but grows with years, not ceas
ing until late old age increasein bulk In adults
it Is generally about five inches long. two and one
half inches in thickness and three and onethird in
ehes in breadth it is divided into two parts by
muscular septlm. and each part is again divided into
an auricle a I'd a ventricle. The of the blood
through the from the right aurice (where all
the venous or impure blood from the system is poured)
into the right ventrcle and thence through the pull
monary arteries into the lungs. Returning from the
lungs it enters the left aurcle and passes into the
left ventrice. whence it is expelled to its long cir
cult through the body Thus does this little organ
pass all the blood of the body through its four cham
bers and that too in less than minutes, without
any rest even during sleep sickness, as long
life lasts. Though only weighing eight to ten ounces;
it is estimated that it force equal daily to
lifting 125 900 tons one foot high and in lifetime,
that propels half million of blood, aud beats
5000, ,OOO 900 times without once stopping. Whence
comes this mighty force which thus quietly and mod
estly, but uniformly, accomplishes such tasks 1t
is from the ryhthmical contraction of its muscles.
But what makes these muscles coatract? 1t is their
vital endowment and that is about all we know. The
will has power the heart 60 to it but
only TO regulate its action and cenrOts contraction
much as the reins in the hands of the jockey guide
the fleet far as discover, its power
is inherent in itself by this that there
lists rritabty within ITSELF to be excited by the
passing blood and this irritabty is derived from the
processes of nutrition organic life of each little
muscular cell. All involuntary muscles (Of which class
the heart is mostly made up) have special en-
duwmens to DE acted upon by certain stimuants. ir-
respective OF all will consciousness lust
cell possesses its peculiar power to convey impressions
it is part of its individual life. Thus when the
muscles of the heart "a health, the presen ce of
blood furnishes the stimulus their contraction
that they drive the blood forth with sufficient force
carry it through its circuit back again the heart
Hence its action depends upon two conditions heal
thy state of the muscles and pure blood, and the
former is determined by the latter to large extent
it may be reduced in general terms to the presence
a certain definitely composed fluid. The enfecbled
pulse in lung disease is natural sequence, be-
the heart is dependent upon the oxygen of the
blood keep up its nutrition Destroy the OF
the air to the lungs and the heart stops because it
cannot repair its waste and hence the muscles lose
their tone or power to act 1t Is thus dependent,
though one of the most independent organs of the
breath taken into the lungs for the air capacity OF
the lungs is greater than is necessary for the
OF blood that is in them at any one time.
If there is deviation in the pulse, there is some
| disorder present. perhaps in the ganglionc system
which longer properly regulates the rhythm of its
pulsatons for example after a debauch great
nervous PrOstration, perchance in some obstruc-
tiOn to the air passages, preventing the proper
ton of the blood But the little tic-ac Of the heart
offers still surer standard for detecting its derange
ments By means of these sounds the physician is
able to detect the nature of many disorders. Each
contraction of the ventrices is called a systole. Ii
marks the passage of jet Of blood from side OF
| the heart to the lungs and from the other to the
general circulation The heart sends out. the
moment pure and impure blood After the little
tick caused by the closure of the valves each sys
tOle there is period of rest in the muscles curing
which tia.e blood is flowing into the auricles. Their
these latter chambers contract, which is called thi
diastole, forcing the blood into the ventrcle. The
time required for the blood to make the circuit of the
body is about twenty seconds, i. e., the tim
for one particle to pass the same point twice As tt
the time required for all the blood pass a certain
point it is estimated in a healthy man to requir
about fOrty-eight seconds. The amount of blood il
a man or woman is generally estimated at about one
eighth of his or her weight, while the little heart il
its largest ventricle only holds five Tn
purely functional diseases are comparatively easy 4
treat, but the organic troubles are generally stub
born and often in the end, fatal. Every heart bea
two millions of blood cells born-every near
beat two millions die; every minute one hundre
and forty millions are created and many carried
TO the grave. cannot move arm or take q ste
without inviting death 1 cannot star watcl
n humming bird without waste of optic nerve an
every flight of fancy, spoken word, strain o
muscle, bas death for a companion " I die daily, ,
yea, more he is not who hour ago, whethe
be will or not, the word is onward d,-onward TO tn
great forever-sently noiselessly, to the great,
known forever. Yours truly,
7. P. TIsDALE, NJ. D.
| Honolulu April I5th, 1873