Atlas of Small Discoveries · 039 V3 · Sonnet

The Carpathian cradle of oil · Bóbrka

Who goes down to the bottom: a person or a tool?

Three cross-sections from Bóbrka in the same phase of work. Change the phase and see what is really at the bottom and how the spoil comes back from there. The drawings are the author's schematic of the principle: no scale, no depth. Limits and sources

Three cross-sections in the same phase of the work cycle

Franek

museum: original drawing: schematic

hand-dug well · c. 1860

Object in the museum: original
This drawing: schematic of the principle

Franek: roof and windlass over the shaft (schematic) Schematic of the principle, not to scale: a roof on two posts over a wide shaft, a hand windlass with a rope descending into the shaft, and a figure at the crank. In phase 3 the crank turns because the bucket is being hauled up.

Drilling rig

museum: reconstruction drawing: schematic

hand-operated drilling rig · 1862 pattern

Object in the museum: reconstruction
This drawing: schematic of the principle

Drilling rig: tripod and rocker beam over a narrow borehole (schematic) Schematic of the principle, not to scale: a tripod over the borehole, a wooden rocker beam on a separate post and a figure standing at its end. The beam tilts first one way, then the other, raising or lowering the tool rod.

Janina

museum: original drawing: schematic

combined shaft · 1878

Object in the museum: original
This drawing: schematic of the principle

Janina: shaft lining and an illustrative structure above it (schematic) Schematic of the principle, not to scale: a low wooden collar over a wide shaft. The structure above the shaft is drawn with a dashed line because the source material does not describe it; it shows only that the tool's blow is transmitted from the surface. A figure stands at the end of the rocker beam.
Franek: cross-section of a wide shaft (schematic) Schematic of the principle, not to scale: a wide, timber-lined shaft reaches the bottom. At the bottom stands a digger with a pick, and beside him a bucket for spoil hung on a rope. In phase 2 the bucket is filled; in phase 3 the full bucket goes up. The zigzag in the shaft marks a shortened drawing: the depth is unknown.
Drilling rig: cross-section of a narrow borehole (schematic) Schematic of the principle, not to scale: a narrow borehole reaches the bottom and nobody stands in it. A rod with a heavy bit is raised and lowered. In phase 2 the bit strikes the rock and the crushed material lies at the bottom of the hole. In phase 3 the material disappears from the bottom; the dashed circle beside the hole means that the way it is removed is not described in the source material. The zigzag in the borehole marks a shortened drawing: the depth is unknown.
Janina: cross-section of a shaft deepened with a drilling rig (schematic) Schematic of the principle, not to scale: at the top a wide, lined dug section whose floor has a ledge, and below it a narrow borehole. The tool descends through the wide section into the narrow hole. In phase 2 the crushed material lies at the bottom of the hole. In phase 3 the material disappears from the bottom; the dashed circle means that the source material does not describe how spoil was brought out of Janina. The zigzag in the borehole marks a shortened drawing: the depth is unknown.

Phase of the work cycle (applies to all three cross-sections)

Playback stops after every click on a phase or on the Pause button.

All three phases of the cycle

Phase 1: at the hand-dug well a person waits at the bottom with an empty bucket, while in both drilling cross-sections there is nobody at the bottom. Phase 2: the digger himself strikes the ground with a pick, while in the drilling rig and Janina only the bit reaches the bottom. Phase 3: the spoil from Franek travels in a bucket on a rope, and from the narrow borehole it is removed in a different way, which has to be checked in the museum's description.

Solid line: an element of the schematic. The V2 descriptions mention only a roof, a hand windlass, a rocker beam and a log lining; the drilling rig's tripod, the posts of Franek's roof and the rocker beam's post are the choice of the drawing's author. Dashed line: a structure above the shaft that the source material does not describe; an illustrative drawing. Copper: whatever moves or carries the spoil. Dashed circle beside the borehole in phase 3: the way the spoil is removed is not described. Zigzag in the shaft: the drawing is shortened, the depth is unknown. Equal drawing height does not mean equal depth. All the drawings are the author's schematic of the principle, not to scale, and not a photograph, a plan or the geology of Bóbrka. Depths and dimensions are deliberately omitted because the source material does not give them.

Franekhand-dug well · c. 1860

Object in the museum: original. This drawing: schematic of the principle, not to scale.

  1. Phase 1 · Preparation

    At the bottom
    The digger and an empty bucket lowered on a rope.
    People
    At the bottom of the wide shaft and at the windlass on the surface.
    Spoil
    Not yet present at this step: the bucket is empty.

  2. Phase 2 · Impact / digging

    At the bottom
    The digger breaks the ground with a pick and a shovel.
    People
    At the bottom, in direct contact with the ground.
    Spoil
    Goes into the bucket standing at the bottom.

  3. Phase 3 · Return / transport

    At the bottom
    The digger stays; the bucket travels upwards.
    People
    At the bottom and at the windlass on the surface.
    Spoil
    Travels in a bucket on a rope, hauled up by a hand windlass.

Drilling righand-operated drilling rig · 1862 pattern

Object in the museum: reconstruction. This drawing: schematic of the principle, not to scale.

  1. Phase 1 · Preparation

    At the bottom
    Nobody; the bit is raised above the bottom of the hole.
    People
    On the surface, at the rocker beam.
    Spoil
    Not yet present at this step of the schematic.

  2. Phase 2 · Impact / digging

    At the bottom
    Only the bit reaches the bottom: it drops and strikes the rock.
    People
    On the surface.
    Spoil
    The rock crumbles under the blows. In the schematic the crushed material lies at the bottom of the hole before it is removed.

  3. Phase 3 · Return / transport

    At the bottom
    The bit is raised; the bottom of the hole is cleared.
    People
    On the surface.
    Spoil
    Removed from the narrow borehole before the next series of blows. How it is brought out: to be checked in the museum's description.

Janinacombined shaft · 1878

Object in the museum: original. This drawing: schematic of the principle, not to scale.

  1. Phase 1 · Preparation

    At the bottom
    The floor of the former hand-dug well, from which a narrow borehole leads; the bit is raised.
    People
    On the surface; there is nobody in the wide dug section in the schematic.
    Spoil
    Not yet present at this step of the schematic.

  2. Phase 2 · Impact / digging

    At the bottom
    The bit strikes the rock below the floor of the former hand-dug well.
    People
    On the surface.
    Spoil
    In the schematic the crushed material lies at the bottom of the narrow deepening before it is removed.

  3. Phase 3 · Return / transport

    At the bottom
    The bit is raised; the wide dug section remains the access to the deepening.
    People
    On the surface.
    Spoil
    The schematic assumes the same method as for the drilling rig. The source material does not describe how spoil was brought out of Janina: to be checked.

Geometric model · not a historical measurement

How much earth has to be removed to open a passage?

A shaft for a person has to be wide; a hole for a bit can be narrow. We calculate geometry only: cross-sectional area times depth. The dimensions of 1.2 × 1.2 m and Ø 0.2 m and the 30 l bucket are model assumptions, not data about specific objects.

The model is calculated for a depth of 20 m. The number field and the slider require JavaScript, so we do not show them without it. With JavaScript enabled, the depth can be changed within the range 5–50 m.

Model range: 5–50 m. The arrow keys, Home and End work on the slider.

Depth 20 m

A · wide shaft 1.2 × 1.2 m (hand-dug well model)
28.80 m³960 fillings of the 30 l bucket
B · hole Ø 0.2 m (drilling rig model)
0.63 m³21 fillings of the 30 l bucket
Janina · combined shaft
The source material has no data on dimensions, so we calculate nothing. This is not 0 m³.

At the same depth the volume of A is approx. 46 times larger than B. The ratio does not depend on depth; only the number of cubic metres and fillings grows.

The bars have a fixed scale: full length is 72 m³ (A at 50 m), so changing the depth changes their length. Bar B is not enlarged; it is at least 1 pixel wide so that it is visible at all. Volume is not the amount of labour or historical output.

Horizontal sections A and B at the same scale (model) A square of 1.2 by 1.2 metres with a small copper circle 0.2 metres in diameter at its centre, at the same scale. The bar below the drawing is 1 metre long.
A model, not a plan of an object. Horizontal section at one scale: shaft A 1.2 × 1.2 m and hole B Ø 0.2 m inscribed in it. The bar below the drawing is 1 m.

A list for looking at on your own

What to recognise in the open-air museum in Bóbrka

Four places described by the museum. No points and no recording of answers: these are questions for your own eyes. On site, the museum's rules apply.

  • 1 · Franekhand-dug well, c. 1860

    • Log lining: how much room did a person going down to the bottom need?
    • A simple roof over the opening: where would the windlass be in such a layout?
    • The difference between a person going down and a tool on a rope.

  • 2 · Drilling rig1862 pattern, reconstruction

    • The wooden rocker beam: by what route does the movement of the hands reach the tool in the hole?
    • The bit goes underground; the person stays outside.
    • Compare the size of the hole with Franek's wide shaft.

  • 3 · Janina1878

    • The structure above the shaft and the layering of methods.
    • A wide dug section at the top, a drilled deepening below.
    • According to the museum's description, still in production. Check this in the descriptions on site.

  • + Forge and workshop1856 and 1864

    • Percussion drilling needed repair facilities right next door.
    • Tools working by percussion required blacksmith and mechanical servicing.
    • The shaft was part of a works that depended on craftsmen.

This list repeats descriptions from the previous version of the page, which were based on museum materials. They were not checked again in this work.

Limits of this cross-section and sources

What the page does not claim

  • The drawings are the author's schematic of the principle of the work. They are not a photograph, a plan or a reconstruction of the geology of Bóbrka, and they have no scale.
  • Depths, shaft dimensions and output are not given because the material of this version does not contain them. When they are added, each value must point to a specific source and period.
  • The three cross-sections have the same height only for the convenience of the layout. The zigzag in the shaft marks a shortened drawing; equal height does not mean equal depth.
  • The dimensions of 1.2 × 1.2 m and Ø 0.2 m and the 30 l bucket are assumptions of the geometric model.
  • The “1862 pattern” drilling rig in the museum is a reconstruction. Franek and Janina are original 19th-century objects according to the descriptions from the previous version of the page.
  • Only the roof, the hand windlass, the rocker beam and the log lining come from the V2 material. The drilling rig's tripod, the posts of Franek's roof and the rocker beam's post are the choice of the drawing's author.
  • The structure above Janina and the way spoil was brought out of the narrow borehole are not described in the material. The structure is drawn with dashes, and the way the spoil is removed is marked only by a dashed circle and the note “to be checked” in the description.
  • We do not describe the risks of working at the bottom, because the previous version gave no source for such claims.

What is missing here compared with V2, and why

  • The method switch was replaced by three cross-sections at once: the difference is visible only in comparison, and nothing is left at the bottom after a change, because nothing is swapped.
  • The zone inspector was replaced by three fixed rows: At the bottom, People, Spoil.
  • The scored checker was replaced by a list of details to recognise.
  • The notebook and saving in the browser were removed. The page saves nothing.
  • Franek's photograph was not embedded because the page is meant to work offline. A link to the source remains.
  • The volume comparison remains as a small model. The bars now have a fixed scale, and bar B is not artificially enlarged.

Sources (links from V2)

Versions and catalogue

Atlas of Small Discoveries · The Carpathian cradle of oil · V3 · Sonnet, an author's draft, not yet accepted. A schematic and a teaching model; historical facts require checking in the sources.