Henry Classification – Step 1: Preparing the Ten-print Card

Lecture Context & Delivery

  • Instructor is using a pre-COVID narrated PowerPoint; Zoom was unavailable at the time.
  • Video may help some students, but the instructor will re-cover every detail live.
  • Course is organized into “steps.” After each lecture you submit work for the relevant step.
  • Today = Step 1 (Preparing the Ten-print card).
    • Submit an answer for Garcia card and Tejeda card.
    • Two answers per step (one for each card).
  • Canvas module items provided:
    • Discussion question (flexible completion).
    • Optional “Henry practice sheets” (self-study; do not submit).
    • Blank ten-print card sheets (reuse for repeated practice).
  • Submission options:
    • Type answers directly into Canvas text box.
    • OR upload a photo/PDF scan of the completed cards.

Big Picture: Why Study Henry Classification?

  • Assigns numeric/letter values to each finger based on pattern type & ridge/tracing data.
  • Historically enabled fast manual filing/retrieval before computers, AFIS, or IDENT/MBIS existed.
  • Vital when arrestees gave false names or lacked ID; cards were filed by fingerprint code, not surname.
  • Sir Edward Henry + colleagues → system used throughout English-speaking world.
    • Spanish-speaking countries use Juan Vucetich system (similar but different; not covered here).
  • Still appears in employment tests/interviews for fingerprint, crime-scene, or forensic positions.
    • Acts as a gate-keeper: proves foundational knowledge of loops, whorls, deltas, cores, ridge counts, etc.

Six Parts of Henry Classification (In Order)

  • \text{Key} \rightarrow \text{Major} \rightarrow \text{Primary} \rightarrow \text{Secondary} \rightarrow \text{Subsecondary} \rightarrow \text{Final}
  • Today’s lecture focuses only on preparatory work (filling out card) so later parts can be computed.

Ten-print Card Layout & Finger Numbering

  • Card displays right hand on top (fingers 1–5), left hand on bottom (fingers 6–10).
  • Finger numbers: {1,2,3,4,5,6,7,8,9,10}
    • 1 = Right Thumb, 2 = Right Index … 5 = Right Little.
    • 6 = Left Thumb, 7 = Left Index … 10 = Left Little.
  • Each small “box” under a rolled print holds a coded description:
    • Lower-left corner = pattern type letter (W, U, R, etc.).
    • Lower-right corner (Boxes 2 & 7 only) must be capital pattern letter (U, R, W, A, T).
    • Upper-left corner = specific whorl subtype (P, CP, DL, AX).
    • Upper-right corner = tracing (O, I, M) if whorl; OR ridge count if loop.

Pattern Types & Standard Symbols

  • Loop → place U (ulnar) or R (radial) in lower-left.
    • Above: write ridge count (integer), e.g. 18.
  • Whorl → place W in lower-left.
    • Upper-left: subtype
    – P = Plain
    – CP = Central Pocket
    – DL = Double Loop
    – AX = Accidental
    • Upper-right: tracing
    – O = Outer (≥2 ridges outside)
    – I = Inner (≥2 ridges inside)
    – M = Meet (within 0–1 ridge)
  • Arch → place a (plain arch) or t (tented arch) in lower-left.
    • No ridge count/tracing needed; box otherwise blank.
  • Optional shorthand: Instead of writing U/R in every loop box, you may draw a slant dash (\ or /) to indicate right-slant vs left-slant—except in Boxes 2 & 7, which must keep the letters for later Henry steps.

Step 1 Workflow (Preparing Card)

  1. Examine each rolled impression.
  2. Determine pattern family (loop, whorl, arch).
  3. For loops: identify ulnar vs radial (based on hand & flow toward ulna/radius).
  4. Locate delta & core; count ridges:
    \text{Ridge Count} = #\text{ of ridges intersected by a straight line core→delta}
  5. For whorls: locate left & right deltas; perform tracing:
    • Drop one ridge below the left delta, follow across to vertical above right delta.
    • Compare with right delta position—classify as O/I/M.
  6. Record symbols in the four corners of each finger box as described above.
  7. Repeat for all ten fingers.

Demonstration: Filled-Out Example (Workbook p. 34)

Card 1 (Top of p. 34)

  • Finger 1 (Ulnar Loop): U / 18.
  • Finger 2 (Ulnar Loop): U / 13.
  • Finger 3 (Ulnar Loop): U / 13.
  • Finger 4 (Plain Whorl): W–P / O.
  • Finger 5 (Ulnar Loop): U / 10.
  • Finger 6 (Ulnar Loop): U / 10.
  • Finger 7 (Ulnar Loop): U / 11.
  • Finger 8 (Ulnar Loop): U / 14.
  • Finger 9 (Ulnar Loop): U / 16.
  • Finger 10 (Ulnar Loop): U / 13.

Card 2 (Bottom of p. 34)

  • Finger 1 (DL Whorl): W–DL / O.
  • Finger 2 (DL Whorl): W–DL / I.
  • Finger 3 (Ulnar Loop): U / 11.
  • Finger 4 (CP Whorl): W–CP / O.
  • Finger 5 (Ulnar Loop): U / 11.
  • Finger 6 (DL Whorl): W–DL / I.
  • Finger 7 (CP Whorl): W–CP / O.
  • Finger 8 (Plain Whorl → actually CP per instructor): W–CP / I.
  • Finger 9 (CP Whorl): W–CP / I.
  • Finger 10 (Ulnar Loop): U / 15.

Whorl Tracing Refresher

  1. Identify both deltas.
  2. From left delta, move one ridge below to start tracing line.
  3. Follow ridge horizontally toward right delta.
  4. Compare finishing point:
    • ≥2 ridges outside right delta → Outer (O).
    • ≥2 ridges inside → Inner (I).
    • Same ridge or ±1 ridge → Meet (M).

Tips, Shortcuts & Conventions

  • Always write capital letters in Boxes 2 & 7 lower-left corner; other boxes may use slant dashes.
  • Never write an “L” for loop; must specify U or R.
  • Arches have no ridge counts or tracings—only lowercase a or t.
  • Consistent labeling means any trained examiner can pick up your card and compute Henry fractions without confusion.

Anticipated Next Steps

  • Wednesday’s lecture: compute Primary & Secondary parts of Henry classification.
  • Requires properly prepared cards from Step 1.

Course Resources & Submission Mechanics

  • Garcia & Tejeda cards are provided in two formats: PDF and Word.
    • If neither opens, email instructor for direct file.
  • Canvas submission interface:
    • “File Upload” tab for photos/scans.
    • “Text Entry” tab: type answers in format such as:
    Garcia – Box1: U 18, Box2: … etc.

Ethical / Professional Implications

  • Mastery of Henry coding demonstrates fundamental understanding of ridge pattern analysis—still valued during hiring in forensic science roles.
  • Serves as a metric to distinguish candidates who have formal fingerprint training vs. those who do not.

Connections to Prior Instruction

  • Earlier lectures already covered:
    • Distinguishing loops (ulnar vs radial).
    • Four whorl subtypes.
    • Plain vs tented arches.
    • Whorl tracing technique.
    • Filling out ten-print boxes.
  • Today revisits those foundations as review while adding Henry system context.

Common Pitfalls to Avoid

  • Mis-labeling radial vs ulnar due to forgetting hand orientation.
  • Forgetting to capitalize letters in Boxes 2 & 7.
  • Using “L” instead of “U/R.”
  • Skipping ridge count for loops or tracing for whorls.

Summary Checklist for Step 1 Submission

✓ Determine pattern & subtype.
✓ Mark U/R or W (with subtype) or a/t.
✓ Add ridge count (loops) or tracing (whorls).
✓ Capital letters in Boxes 2 & 7.
✓ Submit Garcia & Tejeda completed cards via Canvas.