Stoop and roof

1 Stoop with ledge (stoep met luifel)

Running along the front of the house was a private stoop, a couple of inches high, that was covered by an overhanging ledge. The stoop was wide enough for a bench on which the shop's goods could be displayed. The windows had shutters over the lower half, but they could be opened to display more goods. As described In 1867 by G. D. J. Schotel,

This row of windows ran along the width of the whole building above the awning, under which the merchandise was displayed day by day and in the evening the citizen and his family sat pleasantly. Not infrequently, the diligent housewife sat among them to knit, sew, darn, or spin, with the stove under the feet, surrounded by cradle, high chair and children playing, the last Saturday, without the public being annoyed by it.

From Leeuwenhoek's description below, if the ledge was of sufficient size to protect the lower winodws during "a fightful storm", they may have been as wide as the one on the right (click to enlarge) over De Backer van de Hoeck on Delft's Marktplein close to the Nieuwe Kerk.

In Letter 245 of January 8, 1704, to the members of the Royal Society, Leeuwenhoek described a salty rainstorm off the North Sea from the point of view of his office/lab on the floor above it.

On the 8th of December 1703 we had a frightful storm from the Southwest, by which the water, mixed with small parts of chalk and stone, was dashed against the windows of the houses in such a way that the panes were darkened, and although the lower windows of my house, which have uncommonly clean panes and are cleaned very well, were not exposed to the air until about eight o'clock in the morning, though they face Northeast and consequently away from the wind and there is also a ledge (luifel) over them, so that they are protected from the rain. Yet, before half an hour had elapsed, they were covered with so many water particles, and that by the whirlwinds, that they were deprived of most of their transparence. Since those water particles did not evaporate at all, I was firmly convinced that it was sea-water which had not only been dashed by the storm from the sea against the windows, but also spread all over the country.

In order to gain certainty about this, I blew two small glasses such as I considered suitable for making my observations about the water particles adhering to the window pane.

By gently pressing these glasses against the window pane covered with the said water particles, I collected some water on the glasses blown by me.

Roof and gutters

The roof of the Gulden Hoofd was covered with tiles of slate held together with mortar. On the edges of the roof were gutters, made of lead. Leeuwenhoek cleaned them twice a year, yet he found little animals in them. He also used the water that ran from the gutters into the cistern in his back courtyard where he collected rain water.

Letter 18 of 1676-10-09 (AB 26) to Henry Oldenburg contained the first mention of the gutters.

The 26. May [1676], it rained very hard; the rain growing somewhat less, I caused some of that Rain-water, running down from a slated roof, to be gather'd in a clean Glass, after it had been washed two or three times with the water. And in this I observ'd some few very little living creatures, and seeing them, I thought they might have been produced in the leaden-gutters in some water, that had there remain'd before.

By the time he wrote the letter of 1678-12-26 (AB 41) to Constantijn Huygens two years later, he knew the potential of those gutters.

I saw all of these little animals also in ordinary water, but not so many by far as in pepper-water. If in summer I feel inclined to observe various sorts of little animals, I need only take the water that has stood for some days in the leaden gutter on my roof or the water from shallow, stagnant ditches in order to discover miraculous creatures.

The only slow, stagnant ditches were between the fields outside of town.

Letter 59 of 1687-10-17 (AB 104) to Members of the Royal Society explained how he, as did many other people in Delft, collected rain water for everday uses such as cooking and cleaning and, in Leeuwenhoek's case, for scientific use.

Many houses in our City are fitted with stone cisterns underground, into which the rain-water that falls on the roofs of the houses, is conducted by leaden gutters.

Letter 63 of 1688-08-03 (AB 108) to Members of the Royal Society noted yet another use for his roof.

In order to get a clear idea about this, I did take several pieces of dry mortar from the roof of my house, and put this chalk in the fire, long enough to make it red-hot.

Letter 144 of 1702-02-09 (AB 233) to Hendrik van Bleyswijk contained Leeuwenhoek's extended observations of the microbes that he found in the "dirty substance" that remained after the water in his gutters dried.

On the 25th of August I saw that in a leaden gutter in front of my house, in a space about five feet long and seven inches wide, some rain-water had been left, which had a red colour, and since I wondered whether this redness might not be caused by little red animals, as I had sometimes seen this to be the case in some muddy ditches, I took about one drop of this water and looked at it through the magnifying glass; and I discovered a great many little animals which were red and others which were green.

On the 1st of September the substance in the leaden gutter had become as thick as if it had been stiff, wet clay, and however much I did my best, I could not discover any living creatures of the species I had seen before.

On the 2nd of September the weather was also very warm and dry, and at about nine o'clock in the morning I took some of that substance from the leaden gutter, which, now being dried up, did not have the thickness of half a knife's back. It had lain in my laboratory the night before, and I put it in a tube having the thickness of a swan's quill.

How did the little animals get into the gutters? They must have come with the rain.

From these discoveries we may understand indeed that in all falling rain-water which is conducted through gutters into cisterns little animals are to be found, and that into all waters exposed to the air there may get little animals, for by the wind, along with the specks of dust driven into the air, the little animals may be transferred.

On the other hand, little animals which are a hundred and more millions smaller than a coarse grain of sand may be driven on high along with the water particles, if not up to the clouds, at least to a small height, which then at sunset descend and which we call dew. They may also be taken up and transported from the earth by the wind, the more so as we know that with a storm the sea-water is beaten so hard against the shores of the sea that the sea-water particles run down the trunks of trees more than half an hour's walk from the sea, and that this water is found to be salty.