The morning news., 1894-11-11

AAlH hdAuE OF MS testimony mas nuuk upon
the differentiation between the blood Of
man. Notwithstanding that he had made
a deep study and knew that a well de-
fined and important difference existed,
his means OF defining that difference in
his own mind and before the eyes of a
jury was so delicate and so likely to be-
affected even unto inaccuracy by outside
ana slight conditions. that he never felt
Jusuhed in giving positive testimony on
this point. He was in the same position
as that in which other scientists have
found themselves He was morally GER
tain that his ideas were correct and knew
that he could scientifically prove 1t, but
Sun the basis of his reckoning was so
narrow that he was unwilling to stand
upon 1t when human life and liberty were
at stake. He would not swear a mans
life away upon theory.
In explaining Or. Edsons discovery,
two things should be noted. First, the
fact that IL Is as simple as the alphabet
(ot least ens-third OF the important dis
eoVeries have been) and, Second: the for
nation and character Of the blood must
be fully understood Blood is composed
OF watery element and corpuscles. A blood
eorpuscle is the bi-concave disk. Viewed
from the side 1t seems a perfect circle.
Niewod on end it locks like a dumb bell.
The only difference in the blood Of differ
ent creatures is in the size and shape
of the corpuscles. The blood corpuscles
VI q iASll are iaiEt ana nat ana IN A0ElE
center Is small spot or nucleus. The
blood of ell birds and fowls is similar,
but the cOrpuscles are smaller. The blood
Of all animals. aside from birds, FISH and
reptiles, has smaller corpuscles without
the nucleus. The presence of this nucleus
has for many years made 1t possible to
throw out the blood of fishes and birds in
murder cases. Not long ago case at
tracing much attention was tried in Eng
land. The issue hung on the sJatement
of the defense that the blood on a knife
found in the possession of the prisoner
was that Of a turkey. This was abun-
dainty disproven because OF the absence
of the central nucleus in the corpuscles.
Microscopic examination showed this
plainly to the jury, and so no claim had
been made that the blood was that of any
other animal the argument was thrown
out, and the man convicted and hanged
But no point exists by which II is equally
possible to show the difference between
the blood of a human beng I'D the blood
of four-footed beast, 1T has been proven
that a difference exists in the size of the
blood corpuscles of all animals, including
man. The corpuscles have been accurate-
ly measured by microscopic examination
and no doubt whatever exists as to the
truth OF these measurements. 1t has
long been quite possible for scientist
to take the blood found on a prisoners
knife and measure its corpuscles so ex-
hGllN llhl lnC HcleDilSt WOulQ nave no mos
raj doubt in pronounctng them to be hui
man or otherwise. But, as the figures
following will show, the difference in
these measurements Is so slight-a par
ticle Of dust, an unexpected refractton OF
light the most minute optical Illusion
might throw his calculations all awrY--
that no scientist has been willing to swear
to the accuracy of his deductions on this
basis. Here are the measurements: A
blood corpuscle of man has diameter
of 1920 of an inch; the diameter of dogs
blood corpuscle is 1850 of an inch; that Of
a mouse 1880 of an inch; that of an OK
1-45S0 Of an inch; that of sheep $4,000 OF
an inch; that OF a goat 1920 of an inch.
A microscope will measure with fair ac-
curacy to within 100000 OF an inch, but.
as has been said these measurements
are so very delicate that a shade, or the
most minute difference in focus would de-
range and destroy their accuracy. For
this reason they have not been useful in
murder cases. DR.. Edison, In rejecting
! upon this subject not long ago. thought
| Enthusiastically of the advantage that would
| accrue to justice If one only could enlarge
! these corpuscles SO that a minute error
| in measurement would be less important
! Suddenly II occurred to him that by the
! very simplest method they might read
| lily be enlarged, and II is because he
thought of this simple method, and not
| because of any extraordinary learning
involved in carrying it out, that he has
made an important discovery
For many years It has been customary
in cases of forgery to throw the suspect
ed signature in enlarged form upon a
screen with a magic lantern. He saw
| at once that this might as readily bo
done with blood corpusoles as with a
| forged signature. SO he did 1t. First
| he set about to measure 5000 corposcles
Of each kind of blood which seemed most
| likely to be brought into question in mur-
| der cases. He found the diameters to
| be as quoted above. Then by means of
the camera lucida, an attachment to his
microscope, he cast the image of an av-
| erage corpuscle of each variety onto a
| sheet of white paper from which, with
| infinite care, he cut disk exactly corre-
! spending to it in size, but enlarged by
/ means of compasses. He saw to 1t that
| his focus was absolutely the same while
| he carried on this work, and he knew
when he had finished that he had six
| disks of paper which bore exactly the
same relation to each other in point OF
| size that the blood corpuscles did to
each other. He then took these disks
| of paper pasted them on glass and used
| them as a lantern slide. This enabled
him to throw them ON a screen magnifed
as many times as he chose 1t would
| have been simple for him, had he so de-
| sired, TO arrange an apparatus by which ms
| could have made the smallest of them as
| large as the side of his study. He was
| contented, however, with magnifying
them until the largest one measured about
two feet across. II was then possible
| for him to take foot rule and measure
the black spots on his screen with a GER
talnty that the differences in size could,
not be affected by any small, extraneous
influence. This method Of cutting paper
disks he selected as the most desirables
although at first it seemed that pho-
Biography afforded the best menas of ac-
compllshing his ends. The adjustment
Of the Photographic focus however. is
50 delicate matter that he soon real
lied that this would add to the possi-
billties Of inaccuracy and, therefore,
abandoned II.
| When Supt. Byrnes was told of
| DR.. EdsSn's new method he greeted
the news with pleasure. Said he: "Dr.
! Edsens discovery is most importsnt-
Few people viii realize how important II
| Is until they know that within a year at
least fifteen murder cases have occurred
in or near New York in which this matter
OF the Identification Of blood played very
important part I will not say that in any