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Konzept, Inhalt (einschließlich Abbildungen) sowie sprachliche Darstellung dieses Artikels sind urheberrechtlich geschützt. Die Rechte liegen bei PD Dr. Jens Loescher. Die Bildrechte der genannten Archive bleiben davon unberührt. Saarbrücken, den 1. Juli 2012 PD Dr. Jens Loescher Universität des Saarlandes Fachrichtung 4.1. - Germanistik Postfach 15 11 50 D-66041 Saarbrücken

1

Not Theory-laden, not Realistic:

How to see through Swammerdam's Microscope

PD Dr. Jens Loescher Universität des Saarlandes Freie Universität Berlin

Universität des Saarlandes Fachrichtung 4.1. - Germanistik Postfach 15 11 50 D-66041 Saarbrücken

[email protected] http://www.uni-saarland.de/fak4/fr41/germanistik/ [email protected] http://userpage.fu-berlin.de/loescher

Abstract

In this article I will deal with the cognitive practices of the two leading microscopists of the seventeenth century – Swammerdam, Leeuwenhoek – , drawing from Ian Hacking's notion of experimental cognition. Corresponding to this theoretical scaffold I make use of a hint Loraine Daston gave as to material traces of cognitive practices due to reading and writingi.That is why, methodically, I focus on manuscripts in order to track the function of cognitive practices. The manuscript corpus in this article will be the Nachlass of Jan Swammerdam, that is, among others, the papers which constitute the "Biblia Naturae". The Nachlass waspurchased by the Niedersächsische Staats- und Universitätsbibliothek Göttingen on the 27th of September 1784 and is still archived thereii.In section two, I will give a short overview of this manuscript corpus and outline the biographical counterpart of certain traits of Swammerdam's œuvre. In section three, I will elaborate on the theoretical scaffold of my approach. In section four, the cognitive practice of modeling epistemic objects out of magnified images of specimen will be focused. In section five, I will concentrate on the folios of the Nachlass which aid memorizing. Two sidesteps outside the historical narrative proper (to Cajal) will supplement my argument.

1. Introduction .................................................................................................................... 2

2. Swammerdam's Papers................................................................................................... 3

3. Experimental Cognition ................................................................................................. 5

4. Paper Models.................................................................................................................. 8

5. Paper Layers................................................................................................................. 16

6. References .................................................................................................................... 25

2

“Practice — and I mean in general doing, not looking — creates the ability to distinguish

between visible artifacts of the preparation or the instrument, and the real structure that is seen

with the microscope. This practical ability breeds conviction" (Ian Hacking 1985, 137)

“Shapin describes how Leeuwenhoek borrows the prestige of notables to endorse his

observations; but the more elementary fact is that the uncredentialed, socially difficult

Leeuwenhoek achieved authority because of what he saw”. (Catherine Wilson 1995, 171)

1. Introduction

In this article I will deal with the cognitive practices of the two leading microscopists of the

seventeenth century – Swammerdam, Leeuwenhoek – , drawing from Ian Hacking's notion of

experimental cognition. Corresponding to this theoretical scaffold I make use of a hint

Loraine Daston gave as to material traces of cognitive practices due to reading and writingiii.

That is why, methodically, I focus on manuscripts in order to track the function of cognitive

practices. The manuscript corpus in this article will be the Nachlass of Jan Swammerdam, that

is, among others, the papers which constitute the "Biblia Naturae". The Nachlass was

purchased by the Niedersächsische Staats- und Universitätsbibliothek Göttingen on the 27th of

September 1784 and is still archived thereiv.

In section two, I will give a short overview of this manuscript corpus and outline the

biographical counterpart of certain traits of Swammerdam's œuvre. In section three, I will

elaborate on the theoretical scaffold of my approach. In section four, the cognitive practice of

modeling epistemic objects out of magnified images of specimen will be focused. In section

five, I will concentrate on the folios of the Nachlass which aid memorizing. Two sidesteps

outside the historical narrative proper (to Cajal) will supplement my argument.

3

2. Swammerdam's Papers

According to the biographers Lindeboom and Ruestow Jan Swammerdam, who was born in

1637 and died in 1680, needs to take the tragic part on the stage of the scientific revolution of

the seventeenth century. Although trained in the academic subject of medicine in Leiden

Swammerdam suffered from a precariously modest material basis which in fact was supplied

by his father until the latter’s death. Because Swammerdam inherited part of the estate his

financial difficulties seem to have been eased somewhat for the remaining years of his life.

But there must have been another troublesome aspect: Swammerdam was probably isolated

from social life to such a degree that his scientific work served as a sublimation of this deficit.

And Swammerdam was a man of spiritual longing; thus he was caught in the current of the

sect of Antoinette de Bourignon who took to the Netherlands after having been expelled from

France. There is indeed, as his postmortem ‘friend’ and editor Hermann Boerhaave stated, a

basso continuo of worship in his scientific writing, an exhilarated voice praising the creator.

His working style as a scientist did resemble that kind of ardent and possibly self-denying

rigueur. As Boerhaave describes it, Swammerdam must have worked many hours in the sun

dissecting specimen and observing them beneath the microscope with the sweat pouring down

his face, spending the nights taking down notes on what he had seenv. Even in Boerhaave's

sober report the picture resembles that of a religious martyr.

Still, Swammerdam was a trained academic, and there is, somewhat paradox, a host of

allusions, rhetorical topoi, and metaphors adding to the somewhat hypertrophic character of

his letters to the life-long friend Thevenot. Boerhaave who got in possession of the

Swammerdam manuscripts, which Thevenot originally was supposed to publish according to

Swammerdam’s last will, finally managed to edit the material in 1737/1738 under the title

4

‘Biblia Naturae’. Most of the manuscripts were written between 1665 and 1680, some sixty

years earliervi.

Boerhaave did have a hard job. Some papers are written very carelessly (indeed during

experimentation or under conditions of fatigue or bad eyesight) and Swammerdam changes

abruptly between French and Dutch, sometimes in the middle of the sentence. Basically, the

material which is preserved consists of text segments, letters, and copper plates which are

bundled together by folding or glue. Concerning size and quality of paper the missives, for

example the "Tractaat van de beyen" or "L' éphémère", are clearly discriminable. These

manuscripts were transferred into the 'Biblia Naturae'-corpus without major alterationsvii.

Meticulous care was dedicated to the inventories of the illustrations: by Swammerdam, by

Thevenot, finally by Boerhaave. That is why the ‘Biblia Naturae’ contains some fifty pages of

short explanations of the copper plates, a ‘glossary’ of the epistemic objects to be seen which

is the most detailed of its time. There are plenty of corrections and commentaries of

Boerhaave’s hand in the manuscripts, among them two pages of a proof read of the Biblia

with dozens of correcting marks at the margin touching only the Dutch, not the Latin text

segment (fascicle 7) and about eight corrected copper plates which are bundled together in a

pack with most of the other figures of the Biblia-corpus (fascicle 26).

5

3. Experimental Cognition

There are a couple of ‘old chest-nuts’ in research on microscopy, as Liba Taub has put it

(Taub 1999, 732), one of them being the "lost eighteenth century"viii. Indeed, passing the

1680s there is one lonely watch tower of microscopic research: Antoni van Leeuwenhoek who

incessantly sends his missives to the Royal Society. When Gerard LE' Turner stated that the

microscope is "an instrument in search of a theory" (LaBerge 1999, 116), he supposedly

pointed to the fact that, in the seventeenth century, there is no theory for the epistemic

phenomena encountered with the microscope (in contrast to the telescope). There is no grasp

of cellular structures, there is no understanding of microorganisms, there is a very limited

theory of laval metamorphosis – still over-formed by ‘spontaneous generation’ –. The

preference of Newtonian atomism, basically: particles being subject to the laws of gravity, of

mass, of attraction and repulsion forms an undercurrent in quite a few observations of

Leeuwenhoek. That 'Newtonism' proved utterly dysfunctional for microorganisms. On the

whole, theory does not keep pace with experimental output. Therefore, that is the old

chestnut, the experimental output ceases until the beginning of the nineteenth century.

If this is so, why did microscopic observation flourish in the first place? It is not

theory-laden and it is not realistic in the sense that we simply ‘see through the microscope’, as

a famous Hacking-sentence runs. What, then, enabled the five great microscopists of the

seventeenth century — Leeuwenhoek, Swammerdam, Hooke, Malpighi, Grew — to get

started and go on with their work? It is precisely because there is no 'theory-ladenness' and no

‘reality’. Observation and apprehension of the microscopist need to be adjusted ‘from within’

to the environment of the experimental setting (instrument, specimen, light). It is cognitive

6

practices which do the job of closing the lacuna between thing observed, image seen, and

construction of meaning.

There are three major notions of cognition in experimental situations in the

literature: one is the mentioned 'transcendental' approach. The second line of argument rests

on the various versions of distributed cognition, ranging from Ludvik Fleck to Edwin

Hutchins’ 'Cognition in the Wild’ix. Now it is individuals making use of cognitive practices in

order to be able to construct epistemic objects. But these individuals ‘see’ according to

collective schools, mental models or pragmatic frames. Third, in a kind of Sennett-like-

approach a materialistic hyperrealism is put forward: There is a 'dialogue' between the thing to

be worked on and the operating person — sometimes, in the robust version of recently

evolving ‘engineering studies’, the material ‘talks back’ and guides scientific innovationx.

Judging from the manuscripts, I would like to put forward here a brand of

experimental cognitionxi. In the experimental situation the scientist activates certain cognitive

practices which help him bridge a mass of (sense) data and the epistemic thing unfolding. The

transition from ignorance to the "Aha-experience" is in essence a private onexii.

It is important to keep in mind that collectivist and constructivist accounts of cognition

have no terminological armature for the description of specific experimental situations. It does

not make sense to shy away from a 'psychological' or rather: 'processual' brand of cognition,

especially if the material traces on the manuscripts incourage such a viewxiii. I build on

Lorraine Daston’s work on cognitive practicesxiv, but I wish to shift the focus from her a

priori perspective of the epistemic relation between the scientific object and the observing

scientist to specific, ad hoc, 'productive' experimental situations. Cognitive practices are not

the exclusive domain of a 'transcendental scientific self', but also influence singular, 'unique'

encounters between object and observer. They are processed "from scratch" (combined,

transformed, hierarchized) based on environmental, material, and experimental constraints.

7

Since cognitive practices evolve, rise and perish due to an 'improbable' interrelation

of collective thinking styles, transformed ethical habitus, and ad-hoc experimental situations

they need to be described on their specific historical level. Of course, I follow the "anti-

Koyréan" caveat, or rather: taking the terms 'cognition' and 'practice' seriously does not mean

to succumb to a-historical givens. On the other hand, there is no way of escaping the fact that

there is an individual shadow bending over the microscope at the laboratory at night; an

individual in a unique experimental situation. There is no a priori for this kind of practice.

In January 1665, the science-afficionado and diarist Samuel Pepys turned out to be

unable to “come to find the matter of seeing anything by my microscope” (Jardine 1999, 43).

Johann Franz Griendel gave evidence for a very special spontaneous generation in his

“Micrographia nova" (1687): Out of a drop of water beneath the magnifying glass the body

and the head of a frog emanated during the time span of three days. This is evidently

cognition run wild. A theory or thinking style is implemented into the experimental situation

or rather: it is forced on it. There is precisely no cognitive practice involved which would be

of help with isolating segments of the image perceived, forming models of epistemic objects

out of the sense data and memorizing the experimental outcome for future replications.

Consequently, for the skilled microscopists in question here, I suggest three types of cognitive

practices:

'Data Cut'. Isolate segments of the image of the experimental object. Apprehension

of ‘real’ structure and of artifacts.

Modeling. Imaginative forming of 'Gestalts’ with the data.

'Preparation of the Manuscript Page'. Layers of past experimental episodes

superimposed and condensed on the script carrier.

8

4. Paper Models

The microscope is the small brother of the telescope. The ‘early’ microscopes were double-

lens, ‘Keplerian’ optical systems. Of course, microscopes up to the beginning of the

nineteenth century produced a multitude of artifacts: mostly due to spherical and chromatic

aberration. The former is caused by the fact that the refraction at the edge of the lens is greater

than in the center. The latter is pointing to the problem of varying degrees of refraction of

light of different colors. This effect is particularly devastating in compound microscopes

where the light is refracted several times and the image of the specimen therefore is

surrounded by color fringes.

One school of microscopic invention, the English, headed towards more complicated

apparatus, especially with Christopher Cock, Neremiah Grew and, of course, Robert Hooke,

who nevertheless grudgingly conceded that though “offensive to his eyes, tis possible with a

single Microscope to make discoveries much better than with a double one, because the colors

which do much disturb the clear vision in double microscopes is clearly avoided in the single”

(Fournier 1996, 13). Hooke relates to the Dutch current of simplification of the instrument, a

purified version of instrumental magnification, consisting basically of a single spherical lens.

The design of the typical Leeuwenhoek-microscope would be this: a brass block stage

of rectangular cross-section, a specimen pin, a main screw, a single lens. And that is it. Were

it not for the extraordinary quality of the lenses Leeuwenhoek was able to grind (in some of

the nine surviving microscopes modern calibration methods have demonstrated a

magnification up to 120 times of the specimen original) one could speak of spectacles with

some additional equipment.

Swammerdam and Leeuwenhoek lay open the construction of their instrument,

pointing to Hooke’s lengthy description in the ‘Micrographia’. Let us turn to Swammerdam,

to be precise a letter, dated 30th of March 1678 (Lindeboom, 1975, Letter 18, p.98).

9

Figure 1

Swammerdam Nachlass Göttingen, 2°Cod MS med. et hist. nat. 102, Conv.1, Fasc.3, p. 3

recto.

Ik sende ue hier nevens een van myne microscopie glasen, dat tusschen beiden van groote ist, gy

kunt het eens proberen, want ik weet selfs nog niet of het heel goet is. Men gebruykt die al hier

op dese wijs (aa) de tubulus vitreus vol met bloet, (b) het glas van het micros(co)pii, dat in

swaart hout (c) staat (D) het koper beugelken, dat buygen kann, en dat in het hout van het

microsc. heeft de plaats daar syn beweging is (EE), een kopere tubulus (ff) die heen en weer

beweegt en in een gedrayt hout dat swart is, vast staat G. nog een stuxken koper H dat op de

kopere tubulus heen en weer beweegt. en waar op het koper EE vast geklonken is, en rontzom

draijt.

I send you enclosed one of my microscope glasses which is of a moderate size, you may try it

some time, for I do not yet know whether it is very good. One uses it here in this manner (aa)

the tubulus vitreus full of blood (b); the glass of the microscope standing in black (or heavy)

wood (c), the little flexible copper clasp (D9 that has its place in the wood of the microscope

weher ist movement is EE; a copper tubulus (ff) that moves to and fro, and is fixed in a turned

piece of black wood, G. Another little piece of copper H moving to and fro on the copper

tubulus; the copper EE has been rivetted on it and turns around.

10

11

Apart from the beautiful drawing of the compound microscope, this is just the 'usual'

instrument description with paper tools (AA, BB) which link depiction and text. We know

this technique from Boyle's or Hooke's textbooks. Text-depiction pairs simulate the shift from

instrument to object to data table for the novice reader as I have outlined elsewherexv. There is

a deliberate instructing touch to this presentation technique concerning cognitive practices.

Nevertheless, reflections on the instrument, the microscope, also point to the gap between

object and artificial image or artifact ("for I do not yet know whether it is very good"). In

January 1678, two months before his didactic aside to Thevenot, Swammerdam writes

(Lindeboom 1975, Letter 14, 83):

“Nowadays, I believe, the magnifying-glasses are in perfection, and so are the instruments that

one has to use. And I found a very easy way to make all that myself, and I could teach it to

another person in a quarter of an hour. My glasses with which I see the greatest object, are not

greater than as I picture here. But the object should be so near to it that it is nearly touched by

the glass. ".

I believe that you will already have understood how the blood of a man, being outside its veins,

appears as small globuli in this manner. And it remains then still fluid. So that with a

magnifying glass nothing more beautiful is to be seen than that, especially if one lets it run to

and fro, as when every globulus separately is revolving like a circle. One ought to communicate

all these methods and also how one sees this and makes the magnifying-glasses, like you

sometimes say I had promised. However, Sir, a man cannot do everything”.

In Dutch even clearer, Swammerdam explicitly states that there is a need to communicate

‚how to see’ with the microscope. „Alle deese manieren en ook hoe men dit siet en de

vergrootg(l)asen maakt, behoorde men te communiceren”. – Can one communicate how to

see through a microscope? There are three ways: first a 'thick description' of the epistemic

object that is (to be) seen. Second, a depiction of the microscopical image that is objective,

but also didactic. Third, a model, mental or real. The first was done by Swammerdam and his

successors as we have seen with the glossaries. Drawings were Hooke's and Leeuwenhoek's

12

domain or rather their draughtsman's'. In some cases the microscopist himself sketches in actu

while observing the specimen beneath the microscope (Hooke, later Cajal). Leeuwenhoek, at

last, had a wax model of blood corpuscles ready at hand for visitors of his ‘interactive science

museum’ (Taub 1999).

Let us focus the object Swammerdam chose: Red blood cells. Erythrocytes have a

precarious status between theory-ladenness and 'reality' in the seventeenth century.

Leuuwenhoek dealt with them from the beginning of his scientific career until the end of his

life, some fifty years later. He examined his own blood, the blood of frogs and fish, of dogs,

cats, and a lot of other mammals. According to the ruling opinion of his time red blood

corpuscles were supposed to be globules, that means round and soft fluid filled bladders. That

is why they were supposed to be spinning especially when they were isolated from the serum.

The point is that healthy erythrocytes in mammals are swollen disks with a concave

depression in the middle of each side; they are not spherical, but oval and flat. Now,

Leeuwenhoek was struck time and time again by precisely this oddity when examining red

blood corpuscles. They seemed to have a nucleus (‘a light’), they seemed to be flat rather than

round. The mindful scientist – and Leuwenhoek's verba cogitandi abound in his letters – is

confronted with the question, if he has to adapt the theory or the 'cognitive' strategy or if the

observed phenomenon is an artifact. To find out, Leeuwenhoek had his draughtsman depict

the microscopic image directly without his supervision.

13

Figure 2. Taken from Edward Ruestow: "The Microscope in the Dutch Republic. The

Shaping of Discovery", p.195.

On the image the corpuscles appear with an oval shape. In figure four, which was, according

to Ruestow, supervised by Leeuwenhoek, they are clearly globules. "How one sees this"

exactly refers to the cognitive practice of isolating the relevant segment of the image: a data

cut at the right moment. In the no-mans-land between lack of theory and unreliable instrument

the microscopist resorts to a cognitive – and material – practice eventually leading to a

sustainable hypothesis.

The neuroanatomist Ramón y Cajal who ‘invented’ the neuron around 1900 had a

much better instrument. As an award, he was donated a Zeiss microscop with a stereo-

photographic device built in it. Cajal also worked with the camera lucida, which assisted him

with drawing the image while observing the object in the microscopexvi. Cajal – the would be

artist – drew most of his specimen as they appeared beneath the microscope, as projected by

the camera lucida or on the photograph. There is evidence that in certain cases he sketched the

image with his free right hand while looking into the microscope (Garcia-Lopez, Garcia-

14

Marin, Freire 2010). It is the drawings he published as illustrations of his findings more than

photographs.

Figure 3. Taken from Garcia-Lopez/Garcia-Marin/Freire 2010, p.4.

15

Looking at the images the drawings seem to be at variance with the photographs in certain

respects. The drawing transforms the image into a model which imposes a "bias" on

perception, an implicit aesthetic judgment marking certain features and aiding memorization.

The faithful eye and the mindful handxvii of the drawing observer produce an image the

structure of which is more discernible than that of the photograph.

Returning to our red blood corpuscles and thus to a period much earlier I think we are

prepared to see now that isolating and modeling in fact are congruent. By isolating segments

of the image the microscopist is modeling. By both material and cognitive practices he is

communicating the unfolding epistemic object to himself and to others.

16

5. Paper Layers

‘Mental models’ in early science, as a material practice on paper? Yes, especially in relation

to text-depiction-pairs which abound in Swammerdam's letters to Thevenot, not only in the

context of instrument descriptions. In Letter 18, part of which we have analyzed already,

Swammerdam describes a beehive to Thevenot and depicts it (Lindeboom, 1975, Letter 18,

p.99).

Figure 5

Swammerdam Nachlass Göttingen, 2°Cod MS med. et hist. nat. 102, Conv.1, Fasc.2, p.23

recto

I find that the cells (in Dutch: cellule. My remark) of a beehive are not exactly equally big, but

that they differ often; moreover that in every beehive great irregularities do occur, sometimes

the 'cottages' are twice as long as the others wherein they are collecting honey. Moreover, they

are sometimes curved, and sometimes oblique, and are not always arranged in a regular way;

this all contrary to your concept. However, generally spoken the architecture in it is wonderful,

for example to make a hexagon, they divide a circle (aa) in this manner, equally in six parts, that

sometimes do not differ a whit and then the whole building stands on these admirably regulated

lines by which Archimedes undoubtedly would have been dumbfounded, if he had seen it”

17

18

Obviously, the ‘geometrical’ lines, Archimedes would have been dumbfounded by are not on

the microscopic image. Swammerdam adds them to illustrate to his friend what he means by

the ‘architecture’ of the object. A single image is transformed into a model. This model is part

of the semantic shorthand the observer/experimenter uses to communicate to himself and the

reader the structure of the epistemic object.

Another phenomenon that is striking with Swammerdam's papers are about eight copper

plates from the ‘Biblia Naturae’-corpus with handwritten commentaries of Boerhaave. Often

segments of the illustration are highlighted with remarks on misrepresented size, that is: the

comments take pains at communicating correctly 'how this is to be seen'. Now, what is

amazing here is that Boerhaave – acting as a historiographer and preserver of texts written

fifty years earlier – corrects the illustrations according to the present state of the art.

Swammerdam’s text, as Boerhaave was aware, was a historical document already in his times.

The solution for this paradox must be: Boerhaave does not alter the images with relation to

the present state of the art; he corrects them with regard to what he thinks Swammerdam has

seen. The cognitive practices of Data Cut and Modeling need to be communicated as if

author, editor and reader were on the historical level of the experiment.

Figure 4. Swammerdam Nachlass Göttingen, 2°Cod MS med. et hist. nat. 102, Conv.2,

Fasc.26, p. 17 recto.

19

20

Let us return to Cajal once more. In the English translation of his “Reglas y Consejos sobre

Investigación Cientifica: Los tónicos de la voluntad" (1897) we read:

"To bring scientific investigation to a happy end once appropriate methods have been

determined, we must hold firmly in mind the goal of the project. The object here is to focus the

train of thought on more and more complex and accurate associations between images based on

observation and ideas slumbering in the unconscious – ideas that only vigorous concentration of

mental energy can raise to the conscious level". (Swanson/Swanson 1999, 33).

It might be useful to step back for a second. What Cajal apparently suggests here (and is

echoed in Poincaré’s and Jacques Hadamard's reflections on innovation in mathematics for

instance) is a leading role for – mental models. 'Realistic' observation is mentally

reconstructed. Models of the observed specimen are remembered, combined with each other

and with altogether different concepts of the ‘subconscious’. That way scientific innovation

takes place.

With Swammerdam there is, in contrast to Leeuwenhoek’s manuscripts, an amazing

method of organizing this innovation on a material level: layers of text, text-depictions pairs

and comments on the script carrier. Some parts of the Nachlass look as if Swammerdam had

done a preparation of the manuscript page in the sense that it is fixed, 'stained', 'condensed' for

'observation' (reading it again). Thus the cognitive practices of superimposition and

condensing are ‘externalized’ on the palimpsest of the manuscript whereas in the textbook,

the Biblia, they are ‘verbalized’. As an example I suggest Letter 37 dating from September

1679 (Lindeboom 1975, 156).

21

Figure 6

Swammerdam Nachlass Göttingen, 2°Cod MS med. et hist. nat. 102, Conv.1, Fasc.2, p.9

recto

As to the contents of my letter to you four weeks ago: it contained mainly some observations

about the fern which I had made already in the year 1674 and earlier; however, it was neglected

afterwards, please do note that. In my last observations, where I said that the folliculi seminum

are enclosed in some leaflets: that has been written only from a weak memory and although I

looked at it in time; all the small ‘cottages’ were already open, so that I had not all the requisites

at hand that I needed to recognize my error. Now it is like this that the first principles of the

tubercula filicis have the figure of a heart A, which, being like a common membrane or a small

purse, embraces all the follicles equally and hides them. Within this common membrane I have

counted distinctly 178 follicles in some of them. The colour of this ‘tunica investiens' is green in

the beginning, then it gets the colour of muscus on account of the translucent seed ‘cottages’,

and finally it withers, shrinks and bursts. (...) I judge it necessary, Sir, that you add all this to it.”

22

23

Performing an autopsy of the script carrier – the term borrowed from editorial philology

might be in place with the ardent dissectionists here – it is certain that the segment containing

the drawings is of different paper quality than the rest of the script carrier. Consequently, I

think that the illustrations actually are not drawings, but part of a copper plate print inserted in

the letter paperxviii. The demarcation line of copper plate paper and letter paper is clearly

discernible on the original.

Figure 8

24

Taking the text into consideration we find an apt explanation for this ensemble of material

layers. Apparently, Swammerdam has dealt with seeds of ferns some four years earlier and

the copper plates were made then. After that, the material was ‘neglected’, a formulation

Swammerdam is sure to insert in the text post hoc. So, when Swammerdam writes to

Thevenot in August 1679 about the seeds of fern he communicates his observations from

"swakke memorie" — no small wonder given the fact that the observations took place four

years ago. Also the scientist lacks the ‘requisites' for proper observation, the technical

environment is not suitable “om mijn misslag te erkennen”, “to recognize my error”. At this

point there is a clear mark for a new paragraph on the script carrier; usually, Swammerdam

does not set paragraphs apart. 'Het is dan aldus’, ‘Now it is like this’ introduces the correction

of the bad memory in the ensuing text-depiction-pair. Now, the 'old' observation represented

in the illustration and the ‘new’ observation represented in the text merge: in the literal sense,

on the manuscript page. Finally, Swammerdam takes pains to advise Thevenot to “add all this

to it”, that is add the ‘new’ information which was supplied (in part) by the ‘old’ copper plates

to the recent faulty description of the experimental object.

Concluding, I would like to recapitulate shortly what kind of process is taking place

here. The mental images which were accomplished by observation, according to Cajal, are

brought in juxtaposition to the real images depicted in the copper plates. Memory fails, but the

material traces preserve the objective data. Thus a new combination of material and mental

traces unfolds in the text-depiction-pair. This new combination or model is superimposed on

the old faulty one.

Comparing the three manuscripts of this section we end up with a clear picture of

experimental cognition. First, a model is designed. Then, consecutive experimental episodes

are documented in layers on the script carrier. Eventually, these layers are merged in the form

of a palimpsest. An epistemic thing unfolds. It can be seen on paper.

25

6. References

Cajal, Ramón y: "Advice for a young investigator", ed.b. Neely Swanson, Larry W. Swanson,

Massachusetts: MIT Press, 1999.

Cobb, Matthew: "Reading and writing the Book of Nature: Jan Swammerdam (1637-1680),

Endevaour, vol.24/3, 2000.

Fournier, Marian: "The Fabric of Life. Microscopy in the Seventeenth Century", Johns

Hopkins University Press, 1996.

Garcia-Lopez, Pablo; Garcia-Marin, Virginia; Freire, Miguel: "The Histological Slides and

Drawings of Cajal", Frontiers in Neuroanatomy, vol.4, 2010, pp.1-16.

Hacking, Ian: "Do we see through a Microscope?", in: Images of Science. Essays on Realism

and Empiricism, ed. b. Paul M. Churchland, Chicago, 1985.

Jardine, Lisa: "Ingenious Pursuits: Building the Scientific Revolution", London, 1999.

LaBerge, Ann: "The History of Science and the History of Microscopy", Perspectives on

Science, vol.7/1, 1999.

Lindeboom, J.A.: "The Letters of Jan Swammerdam to Thevenot", Amsterdam: Swets &

Zeitlinger, 1975.

Ruestow, Edward G.: "The Microscope in the Dutch Republic. The Shaping of Discovery",

Cambridge, 1996.

Schickore, Jutta: "Doing Science, Writing Science", Philosophy of Science, 75, 2008, pp.323–

343.

Schickore, Jutta: "The Microscope and the Eye: A History of Reflections, 1740–1870",

Chicago: University of Chicago Press, 2007.

Taub, Liba: "Heroes of Microscopy and Museology", Studies in the History and Philosophy of

Science, vol.30, nr.4, 1999, pp.729-744.

Wilson, Catherine: "The Invisible World. Early Modern Philosophy and the Invention of the

Microscope", Princeton, 1995.

i Lorraine Daston: „Taking note(s)“, Isis, vol. 95, no. 3, 2004, pp. 443-448.

ii 2° Cod. Ms. med. et hist. nat. 102. Convoluts one and two (in the followong: conv.). The Swammerdam papers

have been part of the 'Nachlass' of a Gualt van Doeveren, before they were purchased by the university library

Göttingen. The university of Göttingen was founded in 1732 and had a focus on natural philosophy/science from

the beginning.

26

iii Lorraine Daston: „Taking note(s)“, Isis, vol. 95, no. 3, 2004, pp. 443-448.

iv 2° Cod. Ms. med. et hist. nat. 102. Convolutes one and two (in the following: conv.). The Swammerdam

papers have been part of the 'Nachlass' of a Gualt van Doeveren, before they were purchased by the university

library Göttingen. The University of Göttingen was founded in 1732 and had a focus on natural

philosophy/science from the beginning.

v "Bybel der Natuure, door Jan Swammerdam, Amsteldammer. Of Historie der Insecten, tot zeekere zoorten

gebracht: door voorbeelden, ontleedkundige onderzoekingen van veelerhande kleine gediertens, als ook door

kunstige kopere plaaten opgeheldert. Verrykt met ontelbaare waarnemingen van nooit ontdekte zeldzaamheden

in de natuur : II. deelen / Alles in de Hollandsche, des Auteurs Moedertaale, beschreven; hier by komt een

voorreeden, waar in het leven van den Auteur beschreven is door Herman Boerhaave, Professor in de Medicyne

&c. &c. De Latynsche Overzetting heeft bezorgt Hieronimus David Gaubius, Professor in de Medicyne en

Chemie". Leydae: apud Isaacum Severinum, 1737. See Boerhaave's 'Vita auctoris', p.5 passim. The two volumes

are in Dutch and Latin; as it is mentioned in the Titula Gaubius was the translator.

vi A minor note: I found an interesting manuscript of a letter of Leeuwenhoek to Thevenot in the corpus which

has been misplaced (fascicle 25). In this letter Leeuwenhoek claims that he, not Harvey was the first to discover

blood circulation. As far as I can see this letter has not been noticed in the Leeuwenhoek research-community.

vii The "Tractaat von de Beyen" was inserted on pages 367-538 of the Biblia.

viii The term was coined first by Brian Ford in 1973.

ix Ludwik Fleck: "Entstehung und Entwicklung einer wissenschaftlichen Tatsache: Einführung in die Lehre vom

Denkstil und Denkkollektiv", Frankfurt a. M.: Suhrkamp, 1980. Ludwik Fleck: "Erfahrung und Tatsache: ge-

sammelte Aufsätze", ed.b. Lothar Schäfer, Frankfurt a. M.: Suhrkamp, 1983. Ludvik Fleck: "Denkstile und

Tatsachen: gesammelte Schriften und Zeugnisse", ed.b. Sylvia Werner, Berlin: Suhrkamp, 2011. Edwin

Hutchins: "Cognition in the Wild", Cambridge, Mass.: MIT Press, 1995.

x See Chandra Mukerji: Impossible Engineering: Technology and Territoriality on the Canal du Midi, Princeton:

Princeton University Press, 2010. Eugene Ferguson: Engineering and the Mind’s Eye , Cambridge: MIT Press,

1996.

xi Ian Hacking: "Do we see through a microscope?", in: "Images of Science. Esssays on Realism and

Empiricism", ed.b. Paul M. Churchland, Clifford Hooker, Chicago, 1985. Ian Hacking: "Representing and

Intervening", Cambridge, 1983. Ian Hacking: "Experimentation and Scientific Realism", in: J. Ceplin (Ed.):

"Scientific Realism", Berkeley, 1984.

27

xii Some historians of science did conquer these "murky realms" of creativity – an ironical coining of Daston's

(Daston 2008, p.101): Lissa Roberts/Simon Schaffer/Peter Dear (Eds.): "The Mindful Hand: Inquiry and

Invention from the Late Renaissance to Early Industrialization", Dutch Academy of Sciences, Amsterdam, 2007.

Howard Gruber: “On the Relation of Aha-Experiences and the construction of ideas", History of Science, vol.

19, 1981, pp.41-59. W.B. Carlson/M.E. Gorman: “A cognitive framework to understand technological creativity:

Bell, Edison, and the telephone”. In: R.J. Weber/D.N. Perkins (Eds.): "Inventive minds: Creativity in tech-

nology", Oxford: Oxford University Press, 1992.

xiii Larry Holmes was a master in reading laboratory note books on this matter: "narrowly internalistic" (Holmes

1990, 363), as he once ironically labeled himself. Frederic Lawrence Holmes: "Scientific Writing and scientific

discovery", Isis, vol.78, no.2, 1987. Holmes: “Laboratory Notebooks: Can the Daily Record Illuminate the

Broader Picture?”, Proceedings of the American Philosophical Society, vol.134, no.4, 1990, pp.349-366.

Holmes: “Lavoisier and the Chemistry of Life. An Exploration of Scientific Creativity”, Madison: The

University of Wisconsin Press, 1985. Holmes: "The Fine Structure of Scientific Creativity”, History of Science,

vol.19, 1981, pp.60-70.

xiv Lorraine Daston, Peter Galison: "Objectivity", New York: Zone Books, 2007. Especially chapter four, where

Daston and Galison speak of 'personae' of natural philosophers/scientists in a typological way. Cognitive

practices in this view derived from epistemic virtues in the Kantian sense. Daston has been much more

'psychological' with regard to cognitive practices in: Lorraine Daston: "On Scientific Observation", Isis, vol.99,

no.1, 2008, pp.97-110. See also Lorraine Daston: "The Moral Economy of Science", Osiris, vol.10, 1995, pp.2-

24. Lorraine Daston: "Sweet Reason", Isis, vol.75, no.4, 1984, pp.717-721.

xv Jens Loescher: "'Sincere Hand and Faithful Eye': Cognitive Practices in Ensembles of Text and Drawing",

Gesnerus. Swiss Journal of the History of Medicine and Sciences (submitted).

xvi Swammerdam had the camera obscura at hand and used it.

xvii Of course Hooke spoke of the "sincere hand and the faithful eye". Robert Hooke: ’Micrographia’ or some

physiological descriptions of minute bodies made by magnifying glasses with observations and inquiries

thereupon, London: Martyn/Allestry, 1665. pp.9-10.

xviii Copper plates needed to be printed on a special kind of paper which is why illustrations generated by this

method in contrast to wood cuts are always presented in special sections of a book.