First, I want to sincerely apologize for the unacceptably long delay in completing this review. I fully understand how frustrating this must have been. Although changes in my personal circumstances contributed to the delay, I take full responsibility and apologize for the inconvenience caused.

I have thoroughly read this study and greatly enjoyed it. The writing is good, and the arguments are easy to follow. I think the writer has used jargon sparingly, such that the paper should be relatively easy to follow regardless of background. Please find below some minor comments to improve the manuscript.

I have two comments that I would like to see addressed before publication:

1. The manuscript places significant emphasis on Thomas Bonney. It should be made clearer what insights or broader understanding this focus provides.
2. I would like to see the observations and interpretations of the early workers placed more fully in the context of their contemporaries. For example, what did others make of ophiolites and metamorphic rocks at this time? How did people interpret thrust tectonics more broadly? This is done effectively in the section discussing serpentinization, but similar contextualization should be incorporated more thoroughly throughout the paper.

Abstract:

Lines 1-2: grammatical issue. “and is”

Give a little context to Thomas Bonney. Did he work on the Lizard?

Introduction

Clear and useful overview.

Fig 1: Please add a larger map and co-ordinates so people can locate the study area. Misspelling of Traboe Cumulate Complex. I would make thrust arrows on moho much smaller, as these aren’t large scale thrusts but rather indicate a locally variable shear zone.

Lizard district is sometimes capitalized and sometimes not.

2.1 Majendie

Can you please give references for Loe Pool and Helford (e.g., 10 km west of XX). They are not marked on the map, so I cannot judge the extent of the traverse. Perhaps mark Helford estuary on the map, as it is referred to multiple times.

Please give an example of some of his observations which are “congruent with modern surveys”.

2.3. Rogers 1822

It seems Rogers was the first to draw clear distinctions between these four groups? If so, that is worth acknowledging. If not, perhaps the first person to do this could be named.

2.4 De la Breche, 1839

It seems he was the first to note the structural relationship between the serpentine and the amphibolites (i.e., serpentine atop amphibolites). Although he did not invoke thrust tectonics, it is a correct observation. Perhaps worth highlighting more clearly.

2.5 King & Rowney, 1876

Line 275: misspelling of Kynance Cove

Would it be possible to reproduce this composite image (Line 278), given its historical significance?

3.1 Survey of the west and east coasts

Line 323: Misspelling of Pentreath.

For this section, it would be helpful to give a brief overview of the modern interpretation so we can compare it with the views of Bonney. E.g., please outline what modern interpretations include at Pentreath.

Fig. 3: Misspelling of Landewednack.

Table 4: How does the black trap dyke relate to the lithologies outlined in Fig. 3?

3.3. Temporal relationships

Lines 395-397: This petrographic analysis appears to be considerably more advanced than those that preceded it, which is worth emphasizing. It would also be valuable to understand how it compared with other studies of the period—was Bonney ahead of his contemporaries in terms of petrographic technique and interpretation?

What is a “trap dyke”?

3.4. Microscopic examinations

Line 419: “wa” to “was”.

Line 420: “such an interpretation is not at all aligned”

Fig. 5: “light regions”?

4.1. Field and microscopic survey of the schists

It is interesting that Bonney repeatedly interpreted the Landewednack amphibolites as metasedimentary. How did geologists at the time distinguish between metasediments and metaigneous rocks? How does that relate to the invention of geochemical analysis?