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Desiccation And Charring

The problem confronting the fingerprint examiner in treating fingers

which are desiccated or dried and shriveled is that of distending and

softening the skin. Desiccated fingers are generally found to have the

outer layer of skin intact and the ridge detail fairly clear. However,

due to the shrinking, numerous wrinkles will be present, and as the

drying process continues the skin and flesh harden until the fingers

e almost as hard as stone.

It is sometimes possible to distend or swell the flesh by utilizing a

1- to 3-percent solution of sodium hydroxide or potassium hydroxide,

sometimes referred to as caustic potash. As a matter of caution, this

process should be tried with one finger before using it for the

remaining fingers. This point of caution is made because of the

reaction of the potassium or sodium hydroxide, which is actually one

of destruction. While absorption and swelling of the flesh occur, the

disintegrating action of the fluid may result in total destruction of

the flesh.

The finger to be distended is cut from the hand at the second joint

and placed in the hydroxide. When it has resumed its normal size by

the absorption of the solution, it is inked and printed. There is no

set time for this process. The procedure may require a few hours or as

much as several days until suitable results are obtained.

After the finger has been in the solution for about 30 minutes, it

should be removed and examined in order to note the extent of the

swelling and the reaction of the flesh to the solution. If no material

change is noted, the finger is returned to the solution. A close watch

is maintained and the finger is examined from time to time.

The solution may cause thin layers of skin to peel from the finger.

Should this occur, the loose skin is carefully scraped off and the

finger rinsed in water for a few minutes. It is then returned to the

hydroxide for continuation of the process.

If, during the course of an inspection, it is seen that the flesh is

becoming too soft, the finger should be placed in a 1- to 3-percent

solution of formaldehyde or alcohol for several minutes in order to

harden it.

If, after several hours in the hydroxide, the finger has not reached

its normal size, it should be placed in water for an hour or two. This

has a tendency to hasten the swelling. When the finger is removed, it

will be noted that a film has coated the surface. This coating is

carefully scraped off and the finger is replaced in the hydroxide

solution for an hour or so, again scraped if coated, soaked in clean

water, etc. This process of alternating from solution to water,

scraping, and replacing in hydroxide is continued until desirable

results are obtained. The finger is then inked and printed.

The above process will so saturate the finger with solution that it

may be too wet to print properly. Accordingly, the finger may be

dipped into acetone for several seconds, removed, and be permitted to

dry, after which it is inked and printed.

The complete process may take from several hours to as much as 10 days

to secure suitable results. If the final results of the above

procedure are satisfactory with the one finger being tested, the

remaining fingers are given the same treatment. Care must be taken to

identify each finger properly as to right index, right middle, etc.,

to avoid any mixup.

In the event that the reaction of the solution on the first finger

treated is not satisfactory and the operator feels that it would be

futile to continue the process, the finger should be removed from the

solution immediately, washed carefully in water, and placed in

formaldehyde to harden sufficiently for it to be handled without

causing injury to the ridges. The pattern area is cut off in such a

manner that sufficient surrounding surface permits the skin to be

trimmed. Then from the cut side the skin is carefully scraped and cut

to remove the excess flesh. While the cutting and scraping are being

done, from time to time the skin should be soaked in xylene and

massaged for purposes of softening to remove wrinkles. When the skin

is thin enough and sufficiently pliable, the operator places the skin

on his own finger, inks and prints it in the usual manner.

If the results are satisfactory, the same procedure is followed with

the remaining fingers. In the event the resultant inked prints are not

suitable, the skin should be scraped until it is sufficiently thin to

be flattened between two pieces of glass and photographed.

Here again it is pointed out that should there be a poor contrast

between the ridges and furrows when using direct lighting, the skin is

scraped as thin as possible without tearing and it is then

photographed by transmitted light.

There are also included, as cases of desiccation, bodies which have

been burned or subjected to severe heat. Often there are cases where

the skin has become loose but is hard and crisp, or where the finger

has been severely burned and is reduced almost to carbon, yet is firm.

In these instances the ridge detail usually has not been destroyed.

When a body which has been severely burned is located, the problems of

identification should be anticipated. Accordingly, before the body is

removed, a careful examination of the fingers should be made in order

to determine if the removal would, in any way, cause damage to the

fingers. Should it be felt that because of the condition of the body

removal would cause injury to the ridge detail, securing of

fingerprints at the scene, or possibly the cutting off of the hands or

fingers to avoid destruction of the skin, should be considered. An

examination of the fingers may disclose that the outer skin is

hardened and is partially loosened from the flesh. It is sometimes

possible, by twisting back and forth, to remove this outer skin

intact. If this is done, the operator may place the skin on his own

finger, ink and print in the usual way.

If the skin is intact on the finger and is not wrinkled, of course

there is no problem and the usual method is employed to secure


Should wrinkles be present and the skin pliable, tissue builder is

injected into the bulbs, which are then inked and printed.

In the event the wrinkles cannot be removed in this fashion, the

pattern area is cut off and the excess flesh scraped out as before.

While the scraping and cutting are being accomplished, the skin should

be soaked and massaged in xylene to soften. The skin is then placed on

the operator's finger, inked and printed. Should prints made in this

manner be unsatisfactory, the next recourse is photography.

In some instances the fingers of burned bodies will be charred. Such

cases require very careful handling as there is a probability of

destroying or disturbing the ridge detail through mistreatment. In

these instances the procedure is determined by the degree of charring.

In extreme cases the only method of recording is by photographing,

using side lighting to secure the proper contrast of ridges and

depressions. Obviously, no attempt should be made to ink and roll as

the pressure necessary to secure the prints would cause the skin to


In instances where the charring has not reached the extreme stage the

procedures previously set forth should be applied; that is, treatment

of the skin by cleaning, softening, inking and printing, or, finally,

by photographing (fig. 400).

[Illustration: 400. Photograph of charts used in actual case to

establish the identity of a charred body, victim of murder. Chart A

shows skin removed from one of the fingers treated and photographed.

Chart B shows an inked impression of the same finger during victim's