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CHAPTER VII
THE SYLLABIC CLASSIFICATION OF FINGER-PRINTS

Having secured some technical knowledge of how to print, and how to read old finger-prints correctly and with confidence when they turn up again in experience, we are faced now with the problem of how to classify and arrange them for secure preservation and prompt and easy reference, whatever may be our object.

In natural history, in biological facts generally, it is not always easy to define the objects of study strictly, so as to classify them in a practical way. Dealing, however, with printed finger-patterns which are no longer living and changing things, we can hope to secure some of the advantages of a mechanical method. Verworn, in his General Physiology (p. 71) says, very justly: “The fixing of sharp limits and definitions must contain, finally, a more or less arbitrary element, [that], indeed, all limits and definitions are only psychological helps towards knowledge.” Bearing this principle in mind, then, what is the end or object we aim at in a system of finger-print classification?

The objects of identifying a person with some one who has had a name and left a history are of various kinds, as criminal, civil, military, naval, medical, legal, scientific, and insurance purposes. Now, in regard to the use of finger-prints for so many ends in view, a difficulty presents itself. It occurred to me at the outset of my studies, that if the system were to prove trustworthy and useful, even in a minor degree, immense numbers of people in civil life, in army, navy, and mercantile services, or under criminal conviction, would require to have their prints correctly classified, indexed, and arranged for easy reference. How could it be possible in so vast a collection or series of collections to find the one single record wanted? To ransack – unaided by a scientific method of classification – the register of an army containing some 500,000 soldiers would involve the search of a much larger number of cards or sheets than 500,000, according to the duration of regular service, and other possible conditions. To do this would obviously be quite as hopeless and futile a task as groping for a lost needle in a huge hay-field. The problem was to find a system which would facilitate the search in a high degree. Any mere slight assistance would still leave the essential problem unsolved. Now, we might have found in finger-prints mere variety without persistence, or mere persistence without initial variety, and in either case the study could yield little practical result. Again, mere diversity, however persistent, without some elements of underlying resemblance, would not have yielded a basis for such a methodic arrangement as was obviously required.

Much aid came to me from the first, as I have already hinted, from five years’ daily laborious experience in sorting and comparing analogous but artificial patterns in the now obsolete Paisley shawl trade, but in the case now in view colour did not come in as an aid to arrangement. This problem, moreover, was not one of those the poet derides as of mere “gold or clay,” but as I saw, it concerned itself with human lives, and was a task, indeed, that might awaken in the dullest mind a keen sense of moral responsibility in proposing its general use as a new and quite trustworthy method of criminal and other modes of identification. The expert in charge might suddenly be called upon after a little expansion of the system to prove the identity of some evil-doer out of many thousands of possible persons, or to subject a suspected person, on the evidence of a few smudgy streaks of ink or blood, to life-long servitude, or to the irremediable doom of a shameful death. In my own case, at this early stage, the mere possibility of a single serious false identification by a method as yet untried became really terrible to contemplate. After closer study, a clear path began to open through the tangled jungle.

Some familiarity with the equipment of a Far-Eastern printing-press had been afforded me while editing The Chrysanthemum, a monthly magazine published in Tokyo, and devoted to the discussion of Japanese topics of literary, scientific, or antiquarian interest. There were some hundreds of thousands of different forms of type, all classified in so convenient a way that any compositor, by running about a little more actively than would be quite compatible with the grave dignity of an English printing establishment, could soon find the character in whatever form of fount he desired. The idea suggested itself then, that analogous qualities as a basis for classification of the finger-patterns might be revealed by a closer study of Chinese. I do not know Chinese – some years’ close study has convinced me of that. However, each Chinese ideograph, for dictionary purposes, is supposed to be built up around an element called by western lexicographers its key or radical, and of these there are two hundred and twelve. You look for the radical in an unknown character, and then look for that radical in its serial place in the two hundred and twelve. It is a question then, as in finger-prints, of counting strokes, and if the strokes are alike in number in any two instances, of looking then as to how they are arranged. Two characters with the same number of pen-strokes under the same radical or key, may bear quite a different aspect.

A Chinese character is defined and limited, but a finger-print pattern often, or usually, trails off into indeterminate lineations of little value for classification purposes. Hence we seek in the latter to isolate for study the central part of the pattern, where the intricacy of the ramifications usually rises to a maximum. The space covered by the lineations that matter is not usually greater than, often not so wide as, the space occupied by the head of the Sovereign on an English postage stamp. Into this brief compass is compressed a world of significance. A courteous and intelligent young detective in Scotland Yard asked me (in 1886 or 1887, when I was advocating the adoption of finger-print identification), did I really propose to rest identification on features contained within so small a space? I answered him, in pointing to a railway map of London, to consider a net-work of junctions which I indicated, if he would not be justified in saying if that fragment, torn away from its context, were presented to him, that it was a portion of a map of London? After a little scrutiny, he admitted that was so. I had no difficulty in showing him then, that the condensed ramifications of a single finger-print within the very limited area proposed by me were much greater than that of the significant portion of the London map I had just pointed out to him.

In tracking a criminal by a single impression made by a finger, the lineations in so small a space would require to have been clearly imprinted, and to have what many finger-print patterns have not, some notable or significant characteristics about it. Then, when enlarged by photography into a picture of some thirty inches, the measurements from fixed points in the pattern should correspond with those of the person in custody, on suspicion, and the curves should be shown to concur in all their sinuosities. But, in comparing two official imprints of the ten fingers properly and clearly impressed, there should be no difficulty, the points of comparison being overwhelming.

In a possible collection of half-a-million or a million complete sets of finger-prints, can the one before me, of one Thomas Atkins, John Doe, or Richard Roe – under whatever alias – be promptly found if it is there, or, if not there, can its absence be conclusively determined? We have seen, I think, that if two such patterns are confronted, common-sense, and the use of fine measurements, will soon determine whether they be of the same original, or different. The problem, then, is to get this swift and sure confrontation effected.

This problem engaged my attention from the first, or at least not many months after I first began to attend to finger-patterns, and in 1880, when I proposed the printing and recording of the ten fingers of old criminals, I had thought out the same method now outlined in this chapter. It would be impossible to compress all the details necessary to work out the matter officially, without producing a work as large, and perhaps as expensive, as a Chinese dictionary, of which the probabilities are that one or perhaps two copies might be sold.

I laid this matter in outline before Inspector Tunbridge, in his official capacity, in 1888, and again before the War Office Committee, at which an Under-Secretary of the Home Office was present, taking diligent notes. The system now in official use – an improvement made by Sir Edward R. Henry upon Sir F. Galton’s very premature attempt (after a few years’ study in old age) seems to work practically, and therefore I have no criticism to offer, further than to suggest, that if in our system of mercantile book-keeping we had retained the use of Roman numerals, fortunes might continue to be made or lost. I cannot think, however, that our merchants would now give up the Arabic notation for the more complex and clumsy one of ancient Italy. Nor is nature likely to resume her interest in the kangaroo and its future.

Science seeks simplicity, and the Syllabic system, now familiar to every one who uses a telegraphic code, is what I proposed for finger-print registers. In this I simply followed the method of transliterating Japanese and Chinese words into syllables of the Roman alphabet, a condition originally imposed by the old Japanese language itself, in which consonants do not occur singly, but are followed by vowels. Purkinje’s first analysis of the finger-print patterns was not known to me, nor, I believe, to anyone in Europe or America, when I first wrote, although I often in those years suggested that he had probably written something on the subject. My first article in Nature, as sent up, contained a kind of analysis of patterns, with many types, named as whorls, ovals, deltas, loops, junctions, and the like. Some are referred to in the text, but the editor expressed his regret that he had not been able to insert the figures, and their lack made the references in my article obscure. We shall deal with a few of these elementary or typical figures presently. But, let us now come to the main aspect of the syllabic system, in contrast with that devised by Sir F. Galton, who looked upon it as merely ancillary to the anthropometric system of Mons. A. Bertillon, of the French police. Galton was supremely anxious to have his natural facts, his finger-print records, arranged precisely in similar parcels, so that one would not be excessively rich in records compared with its neighbour. Now, what does it matter to the keeper of records, or even to the tax-payer, whether one class of patterns is big or little? The whole absurd complexity arising now, and increasing from year to year, grows out of this essential misapprehension from the first of the vital problems of finger-print classification. Advancing a stage for the moment, let us suppose that a rich register exists, arranged on the syllabic system. A type-writer, not necessarily a very intellectual creature, or a boy-clerk, is in the room, and has the call to find A-bra-ca-da-bra. I use here for convenience only five syllables, representing one hand. The sheets or cards (sheets have been found best by experience) are not separated in bundles except as to a convenient size. It does not take long to look along the shelves till A-bra- etc., is reached, and then the cabalistic word itself. It may prove that there are some ten sheets on the register under this syllabic title. These are transmitted, all in a few moments, to the expert keeper of the records. At a glance an expert eye like his perceives that, perhaps, seven out of the ten can have no possible relation to the case now being enquired into. Of the three, one is perhaps now in prison and cannot be the suspect. Of the two remaining forms, the details of the first two fingers compared may diverge completely in many ways, as determined by counting lines, measuring curves, and so on. I am sure this would be no fancy description, from the many tests I have applied. The whole strain of the recognition lies on the expert, as the strain of the primary classification of records had lain upon him at the time they were being made. Of course, more than one expert might be needed.

It will be noticed, perhaps, that the syllable bra occurs twice on the same hand register. It by no means follows that the finger-print represented by the second bra is very like that of the first one. In the same way, none of the patterns indicated by bra in the cards of similar syllabic index may much resemble the others, even broadly. The pattern simply is of a certain typical form with which bra is to be linked for registration purposes. The same word, so to speak, might be divided in a different syllabic way, thus: —

 
Ab-ra-cad-ab-ra;
Ab-rac-ad-ab-ra; and so on.
 

Hence the necessity of separating the syllables by hyphens.

The divergence of cards will be greater, of course, in the case of a two-hand register, and even in one which comprehended, say, one million of complete sets there would be very few repetitions of the same arrangement of syllables.

One great advantage of the syllabic form is the help given to the memory in transferring the eye from one sheet to others which may be wanted. In the system now in use the symbols do not rivet themselves in the same way, and have a monotony that becomes very tiring.

A general view of the precise intention aimed at in the particular register must determine the extensiveness of the form the register is to compass. Are the numbers likely to be large? Must the registers extend over long periods? Are infants to be kept in view over adult life, if that is reached? Many enquiries of this kind may have to be met before the exact form of the cards or sheets is determined. For such civil and social purposes as life insurances, signatures of deeds, benefit of friendly societies, and the like, a comparatively simple form of register and limited number of finger imprints might be all that would be required for an effective service. The number of cards would not be very great, and the probabilities of personation would likely be restricted to a few local residents whose finger-prints would not often be found even to approach coincidence in a slight degree. To serve such needs, an elementary form of classification would go a long way to overtake ordinary requirements, and would be easy of reference. Few of the difficulties involved in graver conditions of legal identification need be raised as an objection to the general use in banking and ordinary business of this new mode of identification. In forming a system, even with a very wide range, the whole amount of possible complexity in finger-patterns need rarely be called upon, and could not conceivably be exhausted. I speak confidently on this point. The central part of the pattern used is generally very limited, and its area may be widened whenever an enlargement of the primary requirements may demand more complexity in the factors of identification. The ramifications will usually provide variety enough to satisfy the most avaricious register.

Some of the main conditions on which the problem of alphabetic arrangement of the index depends may now be set forth, before we proceed to consider how those conventional syllables are to be formed which indicate patterns.

1. – Distinction is not made between capital and lower-case letters. Simple letters are too soon exhausted in a register of any considerable size. It is obvious that syllables give a much greater variety. As far as possible, commensurate with the dimensions of the register, the syllables should be kept few, simple, compact, and pronounceable. The vowels have the Italian sound. No syllables should contain more than four letters at the utmost.

2. – When a doubt arises as to the proper syllabic reading of a finger-pattern, the earlier letters of the Roman alphabet have the precedence, thus b before d, l before x.

3. – Where the core of a pattern seems to contain two or more clusters of significant lineations, choose for the index syllable that on the right side of the pattern, or, if that is difficult to determine, next that which is highest in position. In such a case, reference to orientation or position refers to the usual or official pattern. In dealing with a smudge of unknown origin, the various possibilities may be tried, assuming relative order of position, as above.

4. – When spaces or figures, such as ovals or circles, are described as “large,” that means wider than the space occupied by two average lineations in that finger-print.

5. – When a finger-pattern has been permanently defaced or obliterated by injury or disease, the missing mark may be denoted by an asterisk (*). If the finger itself is missing, by deformity or mutilation, the asterisk may be encircled with an O. A special compartment of the register might be kept for the reception of all such cases.

6. – Badly-printed or obscure patterns should be held in reserve under a special register classified according to probabilities, aided by cross indexing, and receiving special attention from the higher experts. Official patterns badly printed should at once be repeated, if possible, before confusion arises.

7. – Registers for naval or military, and banking, insurance, and general purposes, should be kept strictly free from any police supervision or control.

The syllables in my system, viewed as lexicographic elements, consist of the ordinary Roman vowels and consonants, the vowels being pronounced, as already said, as in the Italian language. I hold in reserve for additional official purposes a few additional characters, such as the Greek letter delta Δ. Those, however, need not be dealt with in the brief space now available, and would only be required, I believe, in pretty extensive registers. The functions of the conventionally fixed vowels may be better understood after we have sampled a few of the consonants.

As suggested to me by Sir Isaac Pitman’s system of phonography, learned in student years, I arranged the consonants in co-related pairs, thus: p, b; t, d; s, z; h, f; l, r; k, g; v, w; ch (considered as a consonantal character), j; m, n.

I have already pointed out, in dealing with problematic smudges, the need of understanding patterns apart from their actual orientation, which, in an unknown person’s case, may have to be assumed, an attitude which may be determined by official bias. This I have entered more fully upon in the Guide to Finger-Print Identification.

Holding this principle in view, then, let us now take some of the simpler elements of patterns in their very simplest forms, and first consider those grouped under the paired consonants.

Ch and J

Each of these characters is taken to represent a hook with a short leg. Ch is considered as one consonant, and as C is not otherwise wanted, it might have been used alone but for its pronunciation being indefinite. If in the usual form of official imprint the hook, with its curve below, has its short leg facing to the left, thus, J, it is duly represented by the Roman letter of that shape. Observe that if you invert this character, or the type which represents it, thus , it will still point the observer to the J part of the index, on getting the curve set right.

If the short leg of the figure points to the right it comes under Ch. If that happens to confront one in its inverted position it cannot be mistaken for a J figure, but must be looked for under Ch. In all cases the degree or direction of slope in the figures, with a few peculiar exceptions, is of no concern whatever, simplicity and directness of appeal being aimed at from the first.

B and P

These consonants are used to denote a bow. B is the form of a simple bow with one lineation, or if two or more lineations blend into one, they are found on the left side when the convexity of the curve is upwards. P is such a bow, but strengthened, as it were, by one or more blended lineations on the right side, with the same position of the curve. A single line bow is never represented by P. If a bow with a plurality of blended lineations is inverted the reading is not at all affected.

T and D

represent pear-shaped, or battledore-like figures. T denotes such a figure free from attachment to environing lineations, while D stands for a similar figure fixed by its stem. Reverse the position of the figure or turn it upside down and its index quality is not affected.

K and G

represent spindle-like forms, like the above but with two (opposite) stems instead of one. When the figure is moored by one stem it is denoted by K; when fixed at both ends or free at both, by G. Position does not affect these figures.

V and W

These letters stand for whorls or spirals, a kind of figure that often presents much difficulty in finger-print classification. W is a whorl in which, tracing its course from the centre outwards, the pen goes round as a clock-hand turns, or as one looking towards the south perceives the sun to cross the sky. V, on the other hand, is one which, traced in the same way (from within outwards), the pen goes like the clock-hand backwards, or widdershins. Alteration in position makes no practical difference whatever in the reading of those figures into their proper syllables for an index.

O and Q

Although O is a vowel and will be met with again under that class, it is paired in a kind of way with Q.

O denotes a small circle or oval, or opaque, round, or ovoid dot, contained in the core of a pattern.

Q denotes a large circle or oval, containing, usually within itself, other pattern elements of small dimensions.

A circle or ovoid is called large when it occupies a space wider than two average lineations of that finger-pattern in which it occurs. If any doubt exists, by the principle previously mentioned, the figure is referred to O as prior to Q in alphabetical sequence.

M and N

denote figures somewhat resembling mountain peaks, M signifying an outline like that of a typical volcanic peak, while N, though similar, ends in a rod-like form, as of a flag-staff on a mountain top. Invert either of those typical forms and they can be read as before.

A curved cliff-like form, like a wave with a curling crest, may be indicated by the Spanish ñ.

L and R

denote loops in which curvatures are apt to occur. L is a loop, the axis of which is straight, while R is one the axis of which is curved or crooked.

Note that if the legs of a loop widen out beyond the parallels, it is no longer a loop, but a bow or a mountain. They may narrow again and yet remain loops till at last they coalesce, when the figure is transformed into a spindle or a battledore (T, D; or K, G). If the bend is more than that of a right angle, it comes under a new definition, and has some qualities of the whorl or spiral, but is more complex. This need not be entered upon here.

S and Z

I have used these two consonants to indicate certain patterns of a sinuous, undulating, or zig-zag type, the sinuous or purely undulating figures coming under S, but under Z if there is at least one distinct angularity in the pattern.

X

This letter, long familiar to the student of algebra as the symbol of the undetermined, I have reserved for the inclusion of various nondescript and anomalous patterns. Those might become fairly numerous in an extensive register, and in such case there would, no doubt, be found a good basis for fresh sub-classification.

F and H

These two aspirates are made to do useful service, not unlike that of vowels, but not of sufficient interest to be noted in a work like this.

We have thus, with the use of consonants alone, built up a kind of osseous or skeletal system, and we have now but to add the vowels to make those dry bones speak. Let us now consider this element in the syllabic method.

A

This vowel indicates that the interior of a given loop, whorl, circle, or containing pattern of any kind, is empty or vacant. Dealing here only with the simpler conditions in which combinations of vowels and consonants are found, such a figure will be indexed as Ra, La, Ta, Da, as the dominant consonant may require. Such combinations as ar, al, at, ad, etc., may occur, but this would lead us into too many intricate ramifications for a work like the present.

If a pattern is very simple – consisting, for example, of almost parallel lines – it may be denoted by the letter A alone. There are such patterns, and they seem to be somewhat commoner among certain of the negro tribes. I have mentioned in a previous chapter such a pattern on the toe of a lady, and they are typical almost in some monkeys.

E

When we find in the interior of some loop, bow, or other pattern, a group of not less than three short detached lines, or dots, this is to be indicated by the use of E with the ruling consonant, as te, re, me, and so on.

I

stands for a simple detached line, or not more than two parallel lines, in the heart of an encircling pattern.

O

stands for a little oval or circle, or for a round or oval-shaped dot in a core. If the circle, oval, etc. is large, extending over a width occupied by two lineations, then it is treated as a consonantal form. [See also Q.]

U

indicates a fork with two or more prongs within a core, forking towards the bend of bow, loop, mountain, etc. A single prong or spur standing out like a twig is to be distinguished from a fork.

Y

is for a similar fork as described above, but turning its two or more prongs away from the concavity of its enclosing loop, bow, etc.

Besides the direct combination of simple vowels and consonants, which arrangement by itself gives great variety to the index registers, an immense number of syllables are formed by combinations of two or more consonants, while some few of the vowels are treated as long or short where the pattern needs further discrimination; as, for example: —

bra, spo, art, prīd, prĭd, nut, nūt.

By this method the most extensive register is gripped and needs no other index than its own essential structure. If the sheets or cards are kept in their proper sequence, and it would require to be the duty of some one – not necessarily an expert – to see that the alphabetic syllables were kept in serial order, there should be no difficulty in finding the document sought for, if it is there at all.

In translating fresh finger-prints into syllabic form, one has to catch the ideal design, so to speak, in the pattern. The consonantal skeleton, in one of its duplicate forms, is then examined for its containing vowel, and the syllable is complete. The work can be done with amazing rapidity after one is familiar with the patterns, which soon appeal direct to the eye as the type does in a printed book.

Let us now look at a few examples tabulated to show how the system works in detail.

Vowels and Consonants in Syllabic Classification with typical specimens of figure elements.