---
title: "Did Achim Leistner's hand-polishing ('atomic feeling') actually outperform machine methods on the Avogadro spheres, and is the account corroborated beyond the Powerhouse Museum caption?"
type: "question"
status: "open"
date_raised: "2026-07-11T00:00:00.000Z"
writer_model: "claude-opus-4-8"
tags: ["metrology","craftsmanship","tactile-cognition","verification","avogadro-constant"]
---


[[claim-leistner-atomic-feeling-hand-polished-avogadro-spheres]] carries an
`[unverified-historical]` flag. The biographical spine (Leistner, Zeiss-Jena
training in 1953, emigration to Australia in 1957, hand-polishing at CSIRO) is
uncontested and fine at Tier 3–4. The problem is the surprising, load-bearing
element: that the manual "atomic feeling" technique "proved superior to purely
machine-based methods" at the nanometer scale. That is a craft-superiority claim
resting on a single Tier-3 source — the Powerhouse Museum's own object record —
which is below the sourcing floor for a surprising claim that is the emotional
core of the note.

## Why it matters

This is the hinge the whole capture turns on, and its bridge into the vault's
tactile-cognition cluster ([[claim-saunderson-palpable-arithmetic-tactile-calculating-device]],
[[claim-blind-mathematicians-independently-reinvented-private-notation]]) is only
as strong as the "hands beat machines" claim. Until it clears the floor, the note
stays seedling and cannot anchor a draft on touch-exceeding-instrumentation.

## What would answer it

- CSIRO's own account (technical report, precision-optics group history, or a
  named CSIRO scientist's statement) of how the final sphere figuring was done
  and what role manual technique versus instrumented/machine polishing played.
- A metrology or optics-journal write-up (Tier 1–2 — e.g. *Metrologia*, IOP, or a
  peer-reviewed Avogadro Project paper) describing the sphere-figuring process and
  whether hand-lapping outperformed machine methods, and in what respect.
- Any primary interview with or obituary of Leistner from a named journalist or
  scientific society (not a museum caption) attesting to the "atomic feeling"
  nickname and the superiority claim.

## Candidate next moves

Start from the Avogadro Project / International Avogadro Coordination publication
list and search *Metrologia* for the silicon-sphere roundness/topography papers,
which would name the polishing method. Cross-check the Wikipedia article on Achim
Leistner (cited in the capture's hop chain but Tier 4) for its own references and
chase those to primary.

## Progress — 2026-08-13

Followed the Wikipedia footnote chain to primary. Result is mixed rather than a
clean answer:

- The account itself (nickname, general narrative) is now corroborated by two
  more independent named-journalist sources — Wired (Jonathon Keats, 2011) and
  New Scientist (Devin Powell, 2008) — beyond the Powerhouse Museum. See
  [[claim-leistner-atomic-feeling-corroborated-beyond-powerhouse-museum]]. That
  half of this question is answered: yes, corroborated beyond the museum caption.
- The specific "beats machines" superiority claim is echoed by Wired
  independently, but still has no Tier 1–2 primary — see
  [[claim-leistner-hand-beats-machines-claim-lacks-tier1-primary]].
- A Tier-1 *Metrologia* paper (Azuma et al. 2015, via arXiv:1512.05642) shows a
  2013–2014 PTB repolish of the actual AVO28-S5/S8 spheres produced measurably
  *lower* peak-to-valley roundness deviation than "the initial spherical state
  produced by the Australian polishing" — i.e. a later, different process beat
  Leistner's original hand-finish on the one quantitative metric available. See
  [[claim-ptb-repolish-out-rounded-leistners-original-avogadro-spheres]]. Whether
  that PTB process was itself hand-guided or machine-automated is unread
  (Meeß et al. 2014, not fetched this session), so this doesn't settle
  "hand vs. machine" cleanly either — it just shows Leistner's finish wasn't the
  permanent last word.
- Leistner's own technical papers (Leistner & Zosi 1987, *Applied Optics*;
  Leistner & Giardini 1991/92, *Metrologia*) — the primary account in his own
  words — remain paywalled and unread. This is still the strongest lead for
  actually resolving the superiority claim and is why the question stays open
  rather than closing.

Left **open**, not answered: the corroboration sub-question is settled, but the
technical superiority claim this question turns on is still unresolved at the
sourcing floor, and now sits alongside a Tier-1 complication rather than a clean
confirmation.

> [!note] Correction (2026-09-17, propagation-repair)
> The first bullet of Progress — 2026-08-13 above says Wired (Keats, 2011) and New Scientist (Powell, 2008) corroborate "the account itself (nickname, general narrative)." That is out of date. The 2026-08-14 audit of [[claim-leistner-atomic-feeling-corroborated-beyond-powerhouse-museum]] found the phrase "atomic feeling" in **neither** source, and not in the Powerhouse Museum object record either. What the two sources corroborate is **the hand-polishing practice and the feel-the-crystal-structure narrative only**. The nickname's only traceable home is the English Wikipedia article on Achim Leistner (Tier 4). That article credits BBC Four's *Precision: The Measure of All Things*, ep. 2 "Mass and Moles" (4 July 2014), which no vault note has read. So the corroboration sub-question is settled for the practice but not for the nickname. The historical text above is left unchanged.

> [!warning] Correction appended 2026-09-18 (propagation-repair)
> Propagates the CORRECTED 2026-08-16 entry on
> [[claim-leistner-atomic-feeling-hand-polished-avogadro-spheres]], which re-fetched
> and read back the Powerhouse Museum object record in full. Two things the framing
> paragraph above attributes to that record are not in it. The 2026-09-17 block
> above repaired only the nickname-corroboration point; these two stood unmarked
> until now.
>
> **The quotation.** Was: the paragraph above has the record saying the manual
> "atomic feeling" technique "proved superior to purely machine-based methods". Now:
> the record carries no such sentence. Its superiority sentence reads "Leistner's
> fabrication method has been found to be superior to any purely machine-based
> method" — the wording quoted above is a paraphrase set in quotation marks, not the
> source's text.
>
> **The biographical spine.** Was: the paragraph above lists "Zeiss-Jena training in
> 1953, emigration to Australia in 1957" as part of a spine that is "uncontested and
> fine at Tier 3–4" — i.e. resting on that Tier-3 record. Now: the record mentions
> neither Zeiss, nor Jena, nor 1953, nor emigration to Australia in 1957. Those
> details circulate in retellings but have no located source in this vault, so they
> are not carried at Tier 3 by the object record; only the hand-polishing at CSIRO is.
>
> **Unchanged by this correction:** the question itself. The superiority claim still
> rests on a single Tier-3 museum record, still has no Tier 1–2 primary, and still
> sits alongside the Tier-1 PTB-repolish complication
> ([[claim-ptb-repolish-out-rounded-leistners-original-avogadro-spheres]]). The
> source_quote "his hands to feel for any imperfections in the surface of the
> spheres" is verbatim and untouched. Leistner & Zosi 1987 and Leistner & Giardini
> 1991/92 remain the strongest unread lead, and this question stays **open**. The
> historical text above is left unchanged.