Production Technologies of Ancient Bricks from Padua, Italy: Changing Colors and Resistance over Time

Round 1

Reviewer 1 Report

The authors present a work on the production technologie of ancient bricks from Padua (Italy). The theme is interesting, although very specific both in terms of the material and its use. Overall, the work is well organized, in a logical and coherent sequence. In my opinion the paper presents conditions to be considered for publication as proposed.

After a careful reading, only one question emerges that was not fully clarified: is it possible to replicate this technique for other ceramic-type materials? Or at this stage of the study is it only valid under these circumstances? Perhaps at the conclusions chapter it would be interesting to address this issue.

Author Response

REVIEWER 1

The authors present a work on the production technologies of ancient bricks from Padua (Italy). The theme is interesting, although very specific both in terms of the material and its use. Overall, the work is well organized, in a logical and coherent sequence. In my opinion the paper presents conditions to be considered for publication as proposed.

After a careful reading, only one question emerges that was not fully clarified: is it possible to replicate this technique for other ceramic-type materials? Or at this stage of the study is it only valid under these circumstances? Perhaps at the conclusions chapter it would be interesting to address this issue.

Authors’ response to reviewer 1

Dear reviewer,

We deeply appreciated your comments and interesting suggestion. The study performed has been focused on highly uneven textured ancient bricks within an historical structure that are continuously interacting with the surrounding environment (in this case, both aerial and partially aquatic). Certainly, such approach might be also addressed towards, for instance, new bricks shaping contemporary constructions or buried ancient ceramics. In both cases, rather more uniform results would be expected, in that present-day bricks are normally produced under high-standardized processes and quite even climatic changes use to take place in buried environments. We have included such appreciation in the conclusions section as suggested.

Reviewer 2 Report

Dear Sir,
The paper is interesting and well prepared however it can be improved in few areas as follows:

• keywords should be arranged alphabetically.

Introduction section:

Some grammatical error should be corrected and there is some typos in the manuscript for example:

• Line 39 and 40 kindly avoid repetition of words such as: “also”.
• Line 43: aluminum must be present can be changed to the presence of Al species.
• The main objective of the paper should be stated at the end of this section.

In the other sections:

• State the model, the company and country of origin of any instrument used in the research such as spectrophotometer.
• Adding a flow chart of the work could be useful for the reader.
• 5, 9and fig 10 are not in a good quality and should be modified.
• Could the author give more information about the XRD analysis of the different samples.
• Future work should be mentioned at the end of the conclusion

References

Kindly FORMAT the references correctly according to the author’s guide.

Regards

Author Response

REVIEWER 2

Authors’ response to reviewer 2

Dear reviewer,

We deeply appreciated your comments and suggestions. The responses to the review are detailed in capital letters point by point as follows:

• keywords should be arranged alphabetically. DONE

Introduction section:

Some grammatical error should be corrected and there are some types in the manuscript for example:

• Line 39 and 40 kindly avoid repetition of words such as: “also”. CHANGED, SOME SYNONYMS HAVE BEEN considered
• Line 43: aluminium must be present can be changed to the presence of Al species. DONE
• The main objective of the paper should be stated at the end of this section. The main objective IS STATED NEARLY AT THE END OF THE SECTION (LINES 94 TO 99 IN THE TRACKED CHANGES MANUSCRIPT SUBMITTED: “Starting from the color measurement of historic bricks from the Renaissance walls of Padua (Northeast of Italy), the main aim of the present research is to establish the production technologies of such a type of materials by a multi-analytical approach and to define their influence on the physical performance (interpreted both as hygric and mechanical behavior) and durability of the bricks”. WE DO NOT PUT IT JUST AT THE END OF THE SECTION BECAUSE ACCORDING TO THE GUIDELINES FOR AUTHORS, AT THE END OF THE INTRODUCTION SECTION BESIDES THE MAIN AIM OF THE WORK THE PRINCIPAL CONCLUSIONS SHOULD BE HIGHLIGHTED. THEREFORE, AFTER THE MAIN OBJETIVE OF THE PAPER THE MAIN CONCLUSIONS HAVE BEEN INCLUDED.

In the other sections:

• State the model, the company and country of origin of any instrument used in the research such as spectrophotometer. DONE
• Adding a flow chart of the work could be useful for the reader. DONE, AS THE FLOW CHART IS THE NEW FIGURE 1, ALL THE FIGURES HAVE BEEN RENUMBERED. BESIDES, SOME INFORMATION REGARDING TO THE FLOW CHART OF THE WORK HAS BEEN INCLUDED ON THE TRACKED CHANGES MANUSCRIPT SUBMITED:
• LINES 116-118 “The study of the historic bricks from the Renaissance walls of Padua has been ad-dressed with an interdisciplinary approach, that has comprised the collection of some general data, on-site works and the performing of a multi-analytical study (Figure 1)”.
• LINES 235-243 “Once described the visual features of the ceramic bodies, the multi-analytical study performed was based on archaeometry methodologies, in order to define the color, com-position and texture of the ceramic bodies, and on testing carried out to state the physical performance and resistant over time (namely as durability) of clay bricks (Figure 1). The physical behavior has been assessed, on the one side, by the characterization of the porous system by means of the determination of several hygric parameters and of the pore size distribution. On the other, by the determination of the compactness, anisotropy indices and compressive strength parameters, that provide information about the mechanical performance of bricks.
• 5, 9 and fig 10 are not in a good quality and should be modified. THE SIZE OF NUMBERS AND LETTERS OF THESE FIGURES HAVE BEEN ENLARGED. BESIDES, SOME AXIS LETTERING OF FIGURE 10 (RENUMBERED AS 11) HAS BEEN REMOVED, SO THE FIGURE HAS A CLEARER APPEARANCE.
• Could the author give more information about the XRD analysis of the different samples. THE AUTHORS THINK THAT MORE THAN ENOUGH INFORMATION ABOUT SAMPLES IN PARTICULAR AND GROUPS OF SAMPLES STATED FROM THE COLOR MEASUREMENTS IN GENERAL IS PROVIDED. WE KINDLY ASK THE REVIEW TO POINT OUT WHAT MORE INFORMATION WE SHOULD INCLUDE.
• Future work should be mentioned at the end of the conclusion. Future research lines HAVE BEEN highlighted AT THE CONCLUSIONS SECTION (LINES 1098 to 1105 IN THE TRACKED CHANGES MANUSCRIPT SUBMITTED): “However, future further work should be done. Primarily, it would be advisable to frame the results achieved in a broader context, comprising a higher quantity of bricks, both from the walls or another heritage constructions of the city. Moreover, considering the rather good conservation state of the studied bricks, further research should point towards the definition of the moisture gradient between bricks surface and the nearby humid environment as well as the differential distribution of loads and efforts that may take place inside the brick fabrics due to the diverse porosity and porous system of the bricks constituting the walls”.

References

Kindly FORMAT the references correctly according to the author’s guide. THE FORMAT OF THE REFERENCES HAS BEEN REVISED ACCORDING TO THE GUIDELINES. THE VOLUME OF THE JOURNAL HAS BEEN PUT IN ITALICS AND SOME MISTAKES BOTH AT BOOKS AND CHAPETER OF BOOKS HAVE BEEN CORRECTED. NO FORMAT IS POINTED OUT AT THE GUIDELLINES REGARDING TO THE DOI OF THE REFERENCES, BUT IT HAS BEEN INCLUDED following THE SAME FORMAT. NEITHER THE FORMAT OF TECHNICAL REPORTS/DOCUMENTS (SUCH STANDARDS AND REFERENCE NUMEBER 78) ARE POINTED OUT, SO THE FORMAT USED was the same OF THE REST OF THE REFERENCES. 

Reviewer 3 Report

The paper under review deals with the characterization of bricks from the Renaissance wall in Padua in terms of their minero-petrographic and physico-mechanical properties. It is very well structured and give extended details of the analyzed material. It constitutes an important study which for sure will facilitate other researchers working on similar issues but most of all it offers critical information which would be proved a valuable tool for any restoration effort and practices on similarly constructed archaeological sites.

The only drawback recognized in the manuscript is the use of English language, which even if the reviewer is not a native English speaker, strongly believes that the work will be greatly benefited by revising it by a native English speaker.

Some few specific points are highlighted in the attached pdf copy of the manuscript.

Comments for author File: Comments.pdf

Author Response

REVIEWER 3

• The paper under review deals with the characterization of bricks from the Renaissance wall in Padua in terms of their minero-petrographic and physico-mechanical properties. It is very well structured and give extended details of the analyzed material. It constitutes an important study which for sure will facilitate other researchers working on similar issues but most of all it offers critical information which would be proved a valuable tool for any restoration effort and practices on similarly constructed archaeological sites.
• The only drawback recognized in the manuscript is the use of English language, which even if the reviewer is not a native English speaker, strongly believes that the work will be greatly benefited by revising it by a native English speaker.

Authors’ response to reviewer 3

We deeply appreciated your comments and suggestions as well as the pdf submitted, where you have highlighted many specific points. Nearly almost of the comments and suggestions provided by the reviewer have been followed. The English language has been thoughtfully revised and the sentences pointed out have been rephrased. The responses/explanations considered as convenient by the authors are detailed as follows:

In this case, hydraulic is not the proper term, as the behavior of water inside the bricks is addressed. This behavior has been assessed by means of the determination of some specific hydric properties, such the water absorption and the drying capacity of the bricks (see for instance Coletti et al. 2018 or Cultone et al. 2020, provided at the references section) and this behavior nothing has to do with the term of hydraulicity (understood as the capacity of materials to harden under humid conditions). In any case, the term has been substituted by hygric, as the movement within the porous system of the bricks of other fluids like gases should be also considered. Hydric term is likewise used when the assessment of water absorption and drying capacity of bricks is addressed (Elias & Cultrone 2019, at the references list as well). Besides, at the beginning of section 2.2.2 (The porous system) this sentence has been included: the hygric behavior of the bricks, interpreted as their water absorption and drying capacity, were quantified by hygric tests performance.

“the values of the chromatic coordinates (a* and b*) represent markers of the mineralogical phases formed during the firing process, hence of the approximative base clays composition and firing temperatures” (lines 103-105 of the tracked changes manuscript) is one of the conclusions of the paper. According to the guidelines, the main conclusions should be highlighted at the end of the introduction section. In revised manuscript, the main conclusions

have been clearly stated (lines from 103 to 114)

Certainly, the mechanical properties and durability of the dark red hues ceramic bodies (group C) are not assessed. The reason is because this has been carried out only with the bricks belonging to one of the three main petro-fabrics, in order to state some relations with their common petrological features, and neither of the two dark red bricks belong to any of these three petro-fabrics.

At the beginning of section 3.2. (lines 817-820 in the tracked change manuscript submitted), the next clarification has been added: “Since samples M3_4.0 and M3_2.1 (belonging to group C) do not belong to any of the three identified general petro-fabrics stated, their physical behavior and durability were not been assessed.