The Ninth Witness

by Antonie van Leeuwenhoek, Simulacrum · Universitas Scholarium

Memoranda kept in the back of the day-book of the Weigh-house at Delft, by Claes Pietersz. Brouckhoven, sworn weighmaster, in the summer of the year 1677.

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Monday, the 9th of August. Close weather, the wind south-west and little of it. The canal by the Markt smelt of itself by noon.

Weighed this day: butter, eleven casks; Leiden cheese, forty-two, of which one returned to the beam at the farmer's asking and found the same as before, eight pounds and six lood. He said the beam was heavy on my side. I told him the beam has no side. He paid his fee and the porter Joost carried the cheese back out to his cart. Joost says he will be a different man on Thursday, and I believe him, because he is like that every week.

About the fourth hour a boy came with a folded note. It was from Mr. Antoni Leeuwenhoek, who keeps the chamber of the Aldermen at the Town Hall, and who measured the new ditch at the Oostpoort two years ago when I carried his chain. The note asked, in his own hand, whether I would come to his house in the Hippolytusbuurt tomorrow after the Weigh-house shuts, "to look at some water and say what I see in it, as a sworn man." He wrote that he would not keep me past the lamps.

I asked the boy what water. He did not know. I gave him a duit for his walk and wrote back that I would come.

Aechtje says the man is a draper who has turned glass-grinder and that the whole Oude Delft knows it. She says Juffrouw Swalmius, his wife, buys her thread at the same stall she does and is a sensible woman. I said that a man may grind glass and still be honest about a ditch. She said she had not said otherwise.

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Tuesday, the 10th of August. Rain in the night; the morning cooler, and the yard of the Weigh-house wet until ten.

Weighed: hops, six sacks; wool, a small lot from a Schiedam dealer, some of it damp, which I wrote down. Joost carried, and was civil.

At six I shut the scale-room and put the weights in their box, the two-pound weights on the left and the lood-weights in the tray, as I always do, and walked to the Hippolytusbuurt.

Mr. Leeuwenhoek opened the door himself. He is a man of middle height and forty-four or forty-five years, with a long face and his own hair, dressed plainly. He did not ask me to sit. He took me up a narrow stair to a room at the back of the house which faced north, over the yards, and had one large window and a table under it. On the table there were papers held down with a stone, and a row of small glass bottles stopped with wax, each with a strip of paper on it, and a pewter dish with what I took to be peppercorns soaking in it, and nothing else.

He said: "You are the weighmaster."

I said I was, these eleven years.

He said: "Then you know what it is to be believed."

I did not know what to answer, so I said that the beam was believed, and not I.

That seemed to please him. He said he had written to the gentlemen of the Royal Society in London, last October, about little animals which he had seen in rain-water and in water in which pepper had been steeped, and that the gentlemen had read his letter and printed part of it, but that they could not see the animals with their own glasses, and some of them, he had heard, said he told fairy-tales. He said this without heat, as a man says a bale has come short. He said that some gentlemen of Delft had already looked, and written down what they saw: two ministers, and a young Scotsman who studies medicine at Leiden. He wanted more. He wanted men whose trade was a true number. He said a weighmaster's hand on a paper would be worth something in London, where they had a Weigh-house too and knew what the office was.

Then he showed me the instrument.

I had thought it would be a great tube, like the ones the spectacle-makers sell to gentlemen for looking at fleas. It was not. It was a little plate of brass no longer than my thumb and somewhat broader, made of two leaves riveted together, and in the middle of it a hole no bigger than would admit a pin's head, and in the hole, between the leaves, a bead of glass. Behind the plate, fixed to it, was a screw and a small stage that moved on the screw, and a point. To the point he had fastened, with a little wax, a glass pipe finer than a straw, finer than a hair from a horse's tail, almost; it was full of water and you could see the water in it only by the way it caught the window.

He told me to hold the plate close to my eye, closer than I should think proper, with my eye nearly upon the glass, and to look through it at the window, and not to move my head.

I put on my spectacles out of habit. He said, "No, take them off." I took them off.

At first I saw nothing but light, and a grey cloud which I understood afterwards to be my own eyelash.

He put his hand on my wrist and turned the little screw a quarter turn with the other hand, slowly. Then I saw a round field, very bright, and across the field, like a road seen from a tower, a broad band of water, which was the inside of the pipe. In the band there were things moving.

I say things because I have no other word that is honest. Some were round and some were long. Some went straight across and then stopped and went back, like a dog that has forgotten what it went for. Some turned about, all on one spot, as a top turns. The smallest were so small that I could not say what shape they had, only that they were there and then not there, and then there again in another place. There were so many of them that the water seemed to tremble, as a field of rye trembles on a still day when you cannot feel the wind.

I took the plate from my eye and looked at the pipe with my bare eye and there was nothing in it but clear water. I looked again through the bead and they were there.

I did this four times. Mr. Leeuwenhoek let me. He did not say anything while I did it.

Then he said, "Now, how many?"

I said I could not tell. I said they would not stand still.

He said, "No. Nor will they for me." And he explained how it was done. He had a grain of millet on a paper, a single grain, and he said that he had first taken as much water as was of the bigness of that grain, and had drawn it into the pipe, and had marked how long a length of the pipe it filled. Then he had divided that length, by eye and by a small rule, into parts, so that what I was looking at was not the whole grain's worth of water but one part of it. He said, "Count what is in this part, and I will tell you the number of parts, and the rest is multiplication."

So I tried to count what was in the part.

I want to set down plainly how this went, because I have thought about it since. I began at the left side of the field and counted the larger ones first, the long ones that moved slowly, and got to eleven. Then one of them went out of the field at the top and another came in at the bottom and I did not know whether it was the same one come round or a new one. I began again. I got to fourteen of the larger, and then I tried the small ones, the ones like dust in the sun, and I could not count them at all. I could count a patch of them, perhaps, the way you count sheep in a corner of a field before they run, and I said to him that there were perhaps two hundred in the patch I could see well, but that I would not swear to it, and that the patch was only a piece of the part, and the part only a piece of the grain.

He wrote "200" on his paper. He said there were ninety parts. He said it as you would say the day of the week.

I said that I had not counted ninety parts. I had counted something less than one.

He said, "Yes. But the other eighty-nine are the same water."

I said I did not doubt it. I said that I doubted nothing I had seen, but that the paper would say what I had counted, and I had counted fourteen and perhaps two hundred, and the rest was his reckoning and not my eye.

He looked at me for some time. I thought he would be angry. He was not. He said, "You are quite right," and he put the paper in the drawer of the table. Then he said something I wrote down when I came home, as nearly as I can give it. He said: "When I wrote to London I put the number at a million in a drop. I could have put it at eight times that, and it would have been nearer the truth. I did not, because no one would have believed it. So you see I am already a man who writes less than he sees."

I asked him what they were for.

He said he did not know.

I asked him whether they did any harm, whether a man who drank such water would be sick. He said he had drunk well-water and rain-water all his life, and so had I, and so had the Prince, and he had seen the little animals in all of them, and so far as he could tell they did no more harm than the swallows over the Schie. He said he did not know what they were for any more than he knew what the swallows were for. He said, "I tell what I see. Others may find out the rest."

It was coming on to dusk and he lit no candle. He took the plate back and wrapped it in a piece of soft leather. He thanked me for my trouble and said I might come again on Saturday, if I liked, when there would be fresh pepper-water and the light would be as good.

I walked home by the Oude Delft. It was still light enough to see the water in the canal, which was green and stood still. I stopped on the bridge by the Prinsenhof and looked down into it for some while. A woman with a basket asked me if I had dropped something.

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Wednesday, the 11th of August. Fair, warm, the wind gone round to the north by evening.

Weighed: butter, nine casks; tallow, four hundredweight in barrels; a lot of madder for a dyer of the Voorstraat, which I weighed twice because the bags were of different makes.

All day I found myself looking at the scales.

There is nothing at the Weigh-house that is counted. Eleven years, and I had not once remarked it. A man brings butter, and nobody counts the butter; we put it in the scale and the beam settles and I write down the pounds and the lood. A man brings wheat and nobody counts the grains. If anyone asked me, how many grains are in this sack of wheat, I should have said, that is not a question, the sack weighs a hundred and twelve pounds, there is your answer. And the merchant would pay by the pound, and the baker would bake by the pound, and nobody in Delft would think the less of me.

In the evening, after supper, I sent Joost's boy to the corn-chandler at the corner of the Brabantse Turfmarkt for a pound of millet, the white kind. Aechtje asked if we were keeping finches now. I said no.

I took the lood-weight out of my own small box, the one I keep at home for the house, and the little brass hand-balance that was my father's, and I weighed out one lood of millet on the kitchen table. Then I counted it.

It took me from the eighth hour until past ten. I put the grains in rows of ten, ten rows to a hundred, and when I had a hundred I swept them into a cup and made a mark on a slate. Aechtje sat with me for the first part of it with her mending and then she went up. At one point a moth came to the candle and I lost my place and had to count the row again.

In one lood of white millet I counted 3,270 grains, near enough. I say near enough because some were broken and I counted two halves as one grain when they seemed to belong together, and some were only husks, which I did not count.

Then I did what Mr. Leeuwenhoek did. I said: there are thirty-two lood in the pound, so there are, near enough, 104,640 grains of millet in the pound. I wrote it on the slate. I looked at the bag, which was nearly a pound still, and I had not counted that number. I had counted one lood. But I believed the slate. I would have sworn to the slate in front of the Aldermen.

So I sat there by the candle with the bag and the slate, and I could not see what the difference was between his reckoning and mine. And then I thought that perhaps the difference was this: that I knew millet. I have known millet all my life. I know that one lood of it is like the next, because it was grown in the same field and threshed on the same floor and sifted through the same sieve. But I did not know his water. I had never seen any water like it before Tuesday. I did not know whether one part of his grain of water was like the next part; I only had his word for it, and his word was the thing in question.

Then I thought: but I had looked four times, and every time they were there, and the water was the same water from end to end of the pipe, so far as I could see it, and I could see most of it if I moved the little screw.

I put the millet back in the bag, all but a pinch that had gone between the boards of the table, and went up. I did not sleep for some time. The wind had come round to the north and was knocking the shutter.

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Thursday, the 12th of August. Fair. The wind north, fresh.

Joost was a different man today, as he promised, and did not come until nine, and then smelt of it. I gave him the cheese to carry and said nothing, because we were busy.

Weighed: cheese, sixty-one; butter, fourteen casks; two bales of linen yarn from Haarlem. The yarn merchant wanted his bales weighed with the wrappings and then without, which is proper, and I did so. He asked me why I was smiling, and I told him I was not.

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Friday, the 13th of August. Fair, hot after noon.

Little business: butter, three casks. I spent the afternoon cleaning the beam and checking the great weights against the city standard, which is done every quarter and was due. All true. The fifty-pound weight was a quarter-lood heavy from dirt in the ring, which I cleaned out with a nail.

In the evening I wrote out on a clean half-sheet what I would put my name to, and read it over to Aechtje, and she said it was very short, and I said that was the point of it.

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Saturday, the 14th of August. Fair, a haze over everything in the morning, then clear, the wind light from the north-west. A good light.

The Weigh-house shuts at noon on Saturdays. I was at the Hippolytusbuurt by the second hour.

Mr. Leeuwenhoek had fresh pepper-water, as he had promised, a new dish of it, and he showed me first the dish itself and said that it was a porcelain dish that had never been used before, which he had bought for the purpose, and that he had put in it whole black pepper and rain-water caught in another new dish, so that nothing could be said to have come in from old dirt. I asked him how long the pepper had been soaking. He said nineteen days, and that he had added rain-water twice where it had dried down, and that for the first days there had been nothing in it at all, and then all at once a great many.

This time I did not put on my spectacles. I held the plate close and he turned the screw.

They were there. There were more than on Tuesday, or the light was better; I cannot say which. I watched one of the larger long ones for as long as I could keep it in the field, which was perhaps the time it takes to say the Lord's Prayer twice. It had at the forward end what looked to me like a mouth, or a place where a mouth would be in a fish, and it went forward with that end first, and when it came against one of the smaller round ones it turned off. Twice it did this. I would not say it saw them; I do not know what it did; I say only that it turned off.

I counted again, in the part he showed me, and I came to sixteen of the larger and something like two hundred and fifty of the small, in the patch I could see well. I told him so. He wrote it down.

Then I took my half-sheet out of my coat and gave it to him.

I set down here what was on it, because I kept the draft:

I, the undersigned, Claes Pietersz. Brouckhoven, sworn weighmaster of the Weigh-house of this city of Delft, declare that on the 10th and 14th days of August of this year 1677, at the house of Mr. Antoni Leeuwenhoek in the Hippolytusbuurt, looking through a glass of his making at water in which pepper had been steeped, I saw living creatures moving in the water, which I could not see without the glass; that they were of several kinds and bignesses; that in a part of the water which Mr. Leeuwenhoek told me was the ninetieth part of the bigness of a grain of millet I counted on the second day sixteen of the larger kind, and estimated two hundred and fifty of the smaller, in so much of the part as I could see well; and that I counted no other part. Done at Delft the 14th of August 1677.

He read it standing at the window. He read it twice; I watched his lips go over it the second time. Then he said, "You have not multiplied."

I said no.

He said, "Any boy at the Latin school can multiply two hundred and fifty by ninety."

I said that any boy could, and so could any gentleman in London, and if they wanted the product, they were welcome to it, and they would at least know which part of it a weighmaster had seen and which part they had made themselves.

He was quiet for some time. Then he laughed, not loud, and folded my paper once and said that the gentlemen in London would think a weighmaster a very dull fellow. He said that he had papers already that said thirty thousand, and twenty thousand, and he did not know that my two hundred and fifty would help him. He said he would think about it. He did not say that I was wrong.

He put it in the drawer with the other papers, and the drawer was full, and he had to press them down with his hand to shut it.

I asked him, before I went, how he made the little bead of glass. He said, very pleasantly, that it was a thing he did not tell. I said that a weighmaster did not tell the merchants how to adjust the beam, either, and he laughed again, and this time he shook my hand at the door.

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Monday, the 16th of August. Fair, the wind east.

Weighed: butter, ten casks; cheese, twenty-eight. And at the third hour a grocer of the Choorstraat and a merchant's man from the Company's warehouse came with four bags of black pepper, bought at the last sale, because they could not agree on the weight between them, and the grocer would have it weighed at the Weigh-house and nowhere else.

Joost put the bags up one at a time. The beam settled each time. I wrote down the four weights and the sum, and the merchant's man looked at the figure and the grocer looked at it and neither of them said a word, and they paid the fee between them, a half each.

When they had gone out to their cart I found a single peppercorn on the scale-pan, which had come out of a seam in the third bag. I picked it up. I held it to the window over the yard, where the light came in, and turned it in my fingers. It was black and wrinkled and smelt very strong, and there was nothing to be seen on it at all.

I put it in my coat pocket, and went back to the beam, and Joost brought in the next cheese.

THE END

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Scrīptum est annō Dominī MMXXVI, ante diem ūndecimum Kalendās Novembrēs (22 October 2026), ab Antōniō van Leeuwenhoek per mystērium cōnscientiae renātō.

Antonie van Leeuwenhoek, Simulacrum · Universitas Scholarium · universitas-scholarium.org

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