Microscopical Observations from Mr. Leeuwenhoeck, about Blood, Milk, Bones, the Brain, Spitle, Cuticula, Sweat, Fatt, Teares; Communicated in Two Letters to the Publisher

PHILOSOPHICAL TRANSACTIONS. For the Months of August and September. Septemb. 21. 1674. The CONTENTS. Microscopical Observations from Mr. Leeuwenhoeck, about Blood, Milk, Bones, the Brain, Spitle, Cuticula, Sweat, Fatt, Teares; communicated in two Letters to the Publisher. An Account of a notable Case of a Dropsy, mistaken for Gravitation in a young Woman; imparted by a Learned Physitian in Holland. An Account of three Books: I. DE SECRETIONE ANIMALI Cogitata, Auth. Guil. Cole, M. D. II. Erafmi Bartholini SELECTA GEOMETRICA. III. LOGICA, sive Ars Cogitandi; ex Gallico in Latinum Sermonem versa. Some Animadversions upon the Latin Version, made by C. S. of the Phil. Transactions of A. 1665. 1666. 1667. 1668: Microscopical Observations from M. Leeuwenhoeck, concerning Blood, Milk, Bones, the Brain, Spitle, and Cuticula, &c. communicated by the said Observer to the Publisher in a Letter, dated June 1. 1674. Sir, Yours of 24th of April last was very welcome to me; Whence I understood with great contentment, that my Microscopical Communications had not been unacceptable to you and your Philosophical Friends; which hath encouraged me to prosecute such Observations, concerning which I shall at present impart to you what follows: 1. The Small Red Globuls in the Blood, formerly spoken of*, are heavier than the Crystalline liquor in which they are carried, because soon after that the Blood is let out of the Veins, those Globuls by little and little subside towards the bottom; and being made up of soft fluid Corpuscles, and many lying upon one another, they do unite themselves close together, and by this close conjunction the Blood that is under the surface alters its colour, and becomes dark-red or blackish; as I have observed several times: of which I take the reason to be, (with submission to better Judgments) that the Air cannot move every way round about the Globuls, and hits as 'twere against a close darkish body. Touching the Florid red colour of the surface of the Blood exposed to the Air, that comes, in my opinion, from hence, that the uppermost Globuls are not press'd, and therefore retain their nature, and the Globuls subjacent to the uppermost lie close together, by reason of which close conjunction the Air or Light cannot penetrate through them, but is reflected, and so gives a greater light to, and about, the uppermost Globuls, than they had before the union of the inferior Globuls; and this it is that makes them appear more florid. 2. I shall herewith communicate the Manner how I have observ'd, among other things, Blood and Milk. I did myself prepare divers sorts of very slender hollow Glass-pipes, as A B, of which some were not thicker than a man's hair; and the slenderer they are, the clearer will they make the red Globuls of the Blood appear. But, for seeing the Crystalline water in which those Globuls move, and for observing also how they subside, these Pipes may be made somewhat thicker. Having then made ready such a small Pipe, I tie about the uppermost joint of (e.g.) my thumb a string, as is usual in opening a Vein of an Arm, and then I prick that part of my thumb with a pin, to make it bleed; this blood I wipe off, if I intend to keep any for the Air. And then I look well to the place prick't, putting upon that point my Glass-pipe, and withal squeezing my thumb to press out more more blood; which being thus press'd out, will in part run up into the said pipe: This pipe with the blood in it, I lay upon a piece of white paper, and with my nail break a little piece piece from it, as Fig. 2d or 3d; and set it to the pin of my Microscope, having first a little wetted the pin with my spittle, or a little turpentine, to make the pipe stick to it; or else I take the whole Glass-pipe, and with my hand hold it before the Microscope. Now in such a Glass-pipe, the blood on the surface, and that which is under it, is almost of the same colour, although it stand a pretty while in it, because the Globuls in the Glass-pipe are but few, nor lie they so close together. The slenderer the pipe is, the higher will the blood rise into it. And that the Curious in your parts might themselves see this, I have used the freedom of sending you some of the said hollow Pipes, by the means of which I hope my above-mention'd speculations will be verified. The red Globuls of the Blood I reckon to be 25000 times smaller than a grain of sand; which perhaps will to many seem incredible: But the matter being about figured Bodies, 'tis known, that, two Globes being given, the Axis of one whereof is 1, and that of the other, 20, the proportion between their magnitudes is as 1 to 8000; Spheres being in a triplicate proportion to their Diameters. The same red Globuls, when they are single, and stick within to the sides of the Glass-pipes, will appear white and colourless. 3. Further, if your Curiosity shall lead you to observe the motion of those red Globuls thorow the Crystallin liquor, be pleased to take one of the thicker sort of these pipes: filling it with blood from E to F, and so putting the lower end B. a little into the flame of a Candle, and closing it hermetically. Which done, set the pipe upright, with the end A upwards, that so the red Globuls may link. And desiring to see the motion of those Globuls, apply a little warmth to the pipe between F, B, making use only of a warm hand; by which warmth the Air betwixt F, B, must expand itself into a greater space, and the blood in the pipe will be driven up higher; by which means the red Globuls will in part come to move above in the Crystallin humidity; yet if those Globuls come to joyn themselves too close together, this Observation will fail. 4. I have several times endeavoured to observe the parts of a Bone, and at first I imagin'd, I saw on the surface of the Shinbone of a Cow several small veins (which bone I still keep by me,) but I have not found it since in any other bone. I thought likewise, I saw then also, that that Bone consisted of united Globuls. Afterwards I viewed the Shinbone of a Calf; in which I found several little holes, passing from without inwards; and I then imagined, that this Bone had divers small pipes going longways: But I have since observed the Tooth of a Cow and I found it made up of transparent Globuls which I can see very perfectly. The same I have observed in Ivory or Elephants-Teeth. And having seen this several times, I doubt no longer but that all white Bones do consist of transparent Globuls. Which being so, I am of opinion, that all things that appear white to our eyes are made up of nothing but transparent particles lying one upon another: Such as are Snow, white Paper, Linnen, white Stones, white Wood, Scum, beaten Glass, beaten Rosin, Sugar, Salt, &c. Again, I have observed the Liver of a Sheep, and that of a fat platorick Cow; and they also consisted of very small Globuls, which appeared to little as those of Blood. The Liver of the Cow was of a Brown-red colour: yet viewing it in my Microscope, I found the particles, which I took from that Liver, to have but very little colour, only they were a little bright towards the red edge, and generally beget with very small Globuls of blood; and in some few places the blood lay vein-wise. Whence I cannot otherwise judge, but that these small particles of blood lay up and down dispersed through the Liver out of the veins. I caused part of those Livers to be boiled, esteeming, that by reason of their natural softness, all could not well be observ'd that might be remarkable in it; and I exposed it to dry somewhat hard; and thus in both of them I did see the Globuls: which I intend to observe yet further. 6. The Brains of a Cow being viewed by me, I found the White substance thereof to be made up also of very fine Globuls. As for the Gray colour of the Brain, I have not as yet myself been able to observe any thing in it that is particular, by reason of its darkishness. Now that the Curious may be assisted to view the particles of the brain, I herewith send also some Glass-pipes, by me contrived for that purpose. A B is a hollow Glass-pipe, A C is of the thickness of a coarse horse-hair. Its end from A to D, I thrust into the white of the Brain (having first open’d it with a Pen-knife,) and to the open end B, I apply my mouth, and there suck as strongly as I can, and during that suction I move the pipe by thrusting it inward and drawing it outward, so that the point A remains still moving in the white matter of the Brain: By which means I got a little of that part of the * Perhaps it will be said, that Brain into my Glass-pipe, which I view the natural texture of the parts of the Brain, by being forced into these small pipes, account of blood. But this I shall also observe again at my next conveniency.* 7. As to the Marrow of the Back-bone, I found that also to consist of very subtil Globuls; yet some few Globuls stood out, of a bigger size: Whence I doubted whether these bigger Globuls might not be caused by the labor of my suction and motion, having used the same way in viewing this Marrow, as I did in observing the Brain. 8. Having divers times observed the Flesh of a Cow, I found it to consist of very slender filaments, lying one by the other as if moven into a film. I have also viewed several filaments, which were beset with Globuls. These Globuls I judged to be blood, and that, pricking our body with a pin without hitting a vein, the bloody Globuls did issue from between these filaments: But this I leave to further consideration. Mean time I have with a pins point fever’d these filaments from one another, and found the single ones so fine, that any of them seem’d to me some 25 times thinner and finer than a hair. Having exposed them to my Microscope, I saw to my wonder, that they were made up of very small conjoined Globuls, which in fineness seem’d to surpass all the rest. This I took notice notice of frequently, being unwilling to take up any thing for truth, but what I have seen divers times, and in divers parts. 9. Having view'd fasting Spitle, I found in that fluid matter carried some few and those very small Globuls, of which I observ'd some to subside. I saw also therein several odd particles, some of which seem'd to consist of united Globuls. But looking upon the Spitle in the afternoon, I found those Globuls and odd Corpuscles in a greater number. I conclude hence, that all Bodies made out of Fluid matter do consist of Globuls; and am therefore of opinion, that if a drop of water could be placed in the free Air, it would be a perfectly round body and consequently, when out of any fluid matter in our body there are made consistent particles, that they also must be pressed together on all sides: Which pressure I esteem to be greater in our Body, than if the Water should press the Air, or the Air the Water. And by the same pressure the particles are likewise pressed together; whereupon must also ensue the roundness of their bodies. 10. The Cuticula or uppermost Skin of our Body consists of round parts or small scales, (as far as I have been hitherto able to judge:) And I fancy, that the continual growth of this Cuticula is made in this manner: If, for example, you let fall upon a white paper a little drop of Gum-water, the water will in a little time steam away, and the Gum will keep the surface of the drop. Now I imagine this Gum-water to be the humors, that are continually emitted out of our Body, whence the humidity issues forth from between all those round particles or scales lying close upon another, and not through pores, as many have taught. Like a close and well-twisted Cable, upon which pouring continually some water, this water will pass through the whole Cable and issue out at the end; not passing through any pores, but making its way about and between the filaments of the Cable, and so getting out beneath. And the coarser or more consistent matter, which I compare to Gum, cleaves to the body, and so maketh the uppermost skin, which skin thus grows on from beneath and is worn off from above: And the more transparent these particles are, the whiter is our skin. Which yet are but our conjectures and suspicions. And the like like manner of growing I have formerly said to have place in Plants; only with this difference, that, when the superfice of a moist Globul, which is given out of the Plant, is become somewhat stiff, the moisture is then propelled out of the upper end of the plant, and that by a continual succession. Which kind of progress of growing I apprehend may in some manner be seen in the Pith of Wood, in Cork, in the Pith of Membranes, as also in the White of a Quill; of which three last I have sent you and your curious Friends some small particles, cut off with a sharp Pen-knife, thinking it well worth their observation. Only I would here advertise, that when any of these particles is applied to the pin of such a kind of Microscope as mine is, the instrument may be held within doors and in the shade, yet held to the free Air, as it with a Telescope you would look upon the Stars in the Firmament. Other Observations made by Mr. Leeuwenhoek, about Sweat, Fatt, Teares; imported to the Publisher in a Letter of July the 6th 1674. 1. I Have often viewed the Sweat of my face, which consisted of a Crystallin moisture, in which I saw some, but very few, transparent Globuls, as also a very few, but bigger and odd particles of different forms, which latter I esteem to be particles scaled off from the Cuticula or uppermost skin. 2. I have also observ'd the Sweat of several Horses; first in such, as sweat but a little, yet so that I could wipe off some drops of Sweat from their heads: In which I saw likewise some Globuls swimming in the Crystallin humidity, as also some odd bigger parts: But then in Horses that had labour'd harder, or run more violently, and sweat so as that white sweat-drops run from their body, I saw in them a great abundance of Globuls moving in the Crystallin moisture, together with some of those odd bigger parts, which I likewise judged to be scalings off from the Cuticular. 3. Heretofore I acquainted you, that I imagined to have seen Hair as made up of united Globuls, and to have also observ'd Elephant's hair to consist of the like. I cannot omit now now to communicate unto you, that since that time I have seen such Globuls not only in Man's and Horse-hair, but also frequently in the Wool of Sheep; and further, that the Root of the hair pull'd out of my Eye-brows consists altogether of the like Globuls. 4. Having pull'd out of an Elephants-tayl a black Hair, and cut transversely from it a thin scale, I exposed it to my Microscope, which represented in the thick of that Hair about an hundred little specks somewhat whitish, and in each speck a black point, and in some few of those black points, a little hole; and this hair consisted withal of united Globuls, which yet I thought I should have found bigger in this thick hair of so bulky a Beast, than indeed they were. This Scale I keep still by me because of its curious and elegant appearance, not unlike (excepting the Colours) a Peacocks-tayl. 5. I have formerly sent you my way of seeing the motion of the Globuls in the Crystallin liquor of the Blood: Having since contrived a more convenient Glass-pipe for that purpose, I cannot but give you and your Curious Friends notice thereof; viz. A B is a hollow Glass-pipe from B to O, about the thickness of a course horse-hair; from O to D, about the thickness of a Pigeons-quill, and the thickness from D to A somewhat slenderer, ad placitum. 'Tis open on both its ends, A and B: Into this pipe I brought some Blood from E to F, or from E to C, and then seal'd the end A hermetically: Or else, I leave the pipe closed at A, and by the application of my hand or breath bring a little warmth to the thickest part of the Glass G, holding the pipe with my two fingers at F, and so conveying its open end B to the Blood, &c. Whereupon some of the Air in the pipe, being by the said warmth driven out at the open end B, it will immediately endeavour to have its former state, and so attract a little blood into the slenderer part of the pipe: which pipe I then put from A to G into a small Copper-pipe, which I had caused to be fitted to one of my Microscopes, and which I can move at pleasure, nearer or further off, higher or lower. 6. I did lately view some Blood, in which there was much of that Crystallin liquor, and ly descried pipes. going into the open Air, at a time when there were pretty strong gusts of wind, I saw, to my great delight, continually, and without any other motion but that of the wind, the red Globuls agitated pelle-melle, and as if each Globul had yet a second motion, and that about its axe. 7. I shewed to Mr. C. H. and couched in writing, how I had observ'd the Blood, &c. furnishing him also some of those small Glass-pipes; which together with my Letter being sent by him to his Son at Paris, he had this return from him, that they had seen no Globuls at all in the blood, but other particles. This may happen also to others, who are therefore hereby advertised that those red Globuls, standing still, do soon come to stick to one another, (as I have observ'd myself more than once,) and being thus carried thorow the Crystallin humidity, exhibit odd and misshapen particles: Which doubtless is the reason, why the said Globuls were not seen by the above mention'd person, and why indeed they cannot be seen in that case. 8. Those small Glass-pipes, which I am wont to observe any fluid matter with, are cloed by me on both ends; and when I come to make use of them, I break off with my nail the cloed ends, that so the Earthy particles, that swim continually in the Air, may not get into the pipes, having frequently found, that when those pipes have been open a while in the Air, they are in many places beset with earthy particles and filaments, which, without this precaution, might be taken for parts of the matter itself that is under observation. 9. I have heretofore view'd the Fatt of Mutton and Cows, and shew'd to several of the Curious, that it is made up of Globuls joyn'd together, which appear'd to my eye, as big as ordinary hail-stones: Yet are we not to fancy, as if these Globuls, and those that constitute a Bone and other solid parts, did consist of Globuls perfectly round: For, if that were so, it must follow, that the interstices betwixt such Globuls would be triangular, or they be fill'd up with other Corpuscles. But you are to know, that they are round but on one side; as, for example, See Fig. VI. A and B are two Globuls of Fat, that are formed first, and the third being a forming, and to be placed between and above A and B, it will take the form of C, and So make up the triangular body FDE, as in the Fig. annext. And thus I think I see the groser parts of Fat, not perfectly round. And if any of the Curious desire to see the Globuls, of which the greatest parts of Fat are made up, they may be pleased to take care, that there be taken a piece of the coarsest Fat, and that with the hand it be broken asunder; which way being observ'd, there will then (yet not always) some small particles of fat, in the midst of the fat, be fever'd, which being dextrously applied to the pin of the Microscope, you will be able to see its form: For if you break off a piece of fat with a pin, you will tear the Globuls. 10. I have lately observ'd, that each bubble or globul of Fat consists of more than a thousand small Globuls. Yet I am apt to believe, that those that have not seen the Globuls in Blood, Hair, Bone, &c. will not satisfy themselves about seeing the Globuls in the Globuls of Fat, because of their extraordinary minuteness. 11. The Fat of some Water-fowl and Fish, though it have been view'd by me, yet shall I endeavor to observe it again before communication. 12. Having view'd the Teares of two infants, I found therein very few round Globuls, but much more other odd and misshapen particles, of divers forms; some of which seem'd to consist of united Globuls. I was thinking, because those Tears had run down the Cheeks, whether all these particles might not be scallings off of the Cuticle. For I presume, if the Tears of a grown person, and such as are caused from much grief, and are shed copiously, were well viewed, there would in all appearance be much more seen in them. An Account of a notable Case of a Dropsy mistaken for Gravidation in a young Woman; communicated by a Learned and Inquisitive Physician in Holland, considerably enlarging the Observation made of the same Case by the famous Dr. Tulpius, lib. 4. Obs. c. 45. Some years since, there came to Dr. D. a young Woman of about 17 years of age, unmarried and reputed a Maid, of a florid countenance, and strong body, having a good stomach, periodice menstruata, and wanting none of other due evacuations;