Part 13 (1/2)

No set rule can possibly be devised to enable a cla.s.sifier to know with certainty where to draw the line when it is doubtful which cla.s.sification should be given such a print. Individual judgment is the only standard. The test is: _if the pattern, in the opinion of the cla.s.sifier, is rolled to only a normal width, it should be cla.s.sified as it appears. If it seems to be rolled to a width beyond the normal degree, it should be cla.s.sified as if rolled only to the normal degree_. Age, weight, size of fingers (as seen in the plain impressions), heaviness of the ridges, and experience of the technician in taking fingerprints are all factors in arriving at the correct conclusion. The necessity for exercising the utmost care in dealing with this type of pattern cannot be too highly emphasized.

[Ill.u.s.tration: 345]

[Ill.u.s.tration: 346]

The patterns in figures 345 and 346 also have a second loop near the edge of the impression. In these two patterns, however, the second loop is very near the delta and consequently will almost invariably appear even though not rolled to the fullest extent. The foregoing rule is not applied to this type of impression. Both are cla.s.sified as a whorl and referenced to a loop to take care of the rare contingency of nonappearance.

CHAPTER IV

_The Cla.s.sification Formula and Extensions_

_The cla.s.sification formula_

At this point it is necessary to mention that when prints are cla.s.sified, markings are indicated at the bottom of each finger block to reflect the type. The following symbols are used:

- Under the index fingers the appropriate capital letters should be placed for every pattern except the ulnar loop.

- Under all other fingers, the appropriate small letter should be placed for every pattern except the ulnar loop and the whorl as follows:

Arch a Tented Arch t Radial Loop r

- Ulnar loops in any finger are designated by a diagonal line slanting in the direction of the loop.

- Whorls in any finger are designated by the letter ”W”. The cla.s.sification formula may be composed of the following divisions:

1. Primary 2. Secondary 3. Subsecondary 4. Major 5. Final 6. Key

The positions in the cla.s.sification line for these divisions when completely applied are as ill.u.s.trated:

Key Major Primary Secondary Subsecondary Final -------------------------------------------------------------------------- Divisions Cla.s.sification Cla.s.sification Cla.s.sification

20 M 1 U IOI 10 -------------------------------------------------------------------------- L 1 U IOI

Second subsecondary cla.s.sification Key Major Primary Secondary Subsecondary Final -------------------------------------------------------------------------- Divisions Cla.s.sification Cla.s.sification Cla.s.sification

SLM --- MMS 4 O 5 U IOI 10 -------------------------------------------------------------------------- I 17 U IOI

THE PRIMARY CLa.s.sIFICATION: For the purpose of obtaining the primary cla.s.sification, numerical values are a.s.signed to each of the ten finger s.p.a.ces as shown in figure 347. Wherever a whorl appears it a.s.sumes the value of the s.p.a.ce in which it is found. s.p.a.ces in which types of patterns other than whorls are present are disregarded in computing the primary.

The values are a.s.signed as follows:

Fingers No. 1 and No. 2 16

Fingers No. 3 and No. 4 8

Fingers No. 5 and No. 6 4

Fingers No. 7 and No. 8 2

Fingers No. 9 and No. 10 1

[Ill.u.s.tration: 347]

LEAVE THIS s.p.a.cE BLANK| |s.e.x +--------------+ | |__________ |FBI No. | | |RACE +--------------+ |LAST NAME FIRST NAME MIDDLE NAME| -----------------------------|----------------------------------+---------- SIGNATURE OF PERSON |CONTRIBUTOR |ALIASES |HT. |WT.