Observations on the development of the blood corpuscles in the chick, with the various changes which they present from their first appearance to their full development : with some remarks on these changes / by William Macleod.
- Date:
- [1842]
Licence: Public Domain Mark
Credit: Observations on the development of the blood corpuscles in the chick, with the various changes which they present from their first appearance to their full development : with some remarks on these changes / by William Macleod. Source: Wellcome Collection.
Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.
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![1 required to the observations made, not to make them. In * support of the second cause, I am unable to bring forth imme- I diate facts to prove that water was used, but I think the follow- i ing statements are sufficient to make us believe that such was the case. At the time De. Tojye wrote his paper, it was not.^ 1 known that water could change the appearance of the blood-cor- ] puscles, at least we have no statement, as far as I am aware, to ithat effect. Now, as these bodies cannot be examined properly ' without the serum in which they are contained being diluted, (either with more serum or some other fluid; and as water is al- ' ways at hand, whilst serum is not; and, moreover, as many of (the appearances described by De Torre may be seen on diluting \ the blood with water, we have every reason to believe that this I fluid was used for that purpose. That the blood-corpuscles and 1 their parts have an attraction or affinity for each other, almost i all microscopic observers grant. To this property of the blood I corpuscles do we owe almost all the errors contained in Sir Everard Home’s description of the formation of the different or- jganic structures. De Torre himself observed this property, and to it he indeed refers many of the appearances which he saw. He says, “ and the others formed by their mutual attraction^ a I lateral union, like the pipes of an organ.” I have frequently seen 1 the blood-corpuscle, in its several stages of development, form ; a great number of the appearances which De Torre describes, ’ with many others, “ and they all separated as easily from each t other as if united simply hy contact'' These three causes seem to ime fully to account for the different appearances of the blood-cor- ipuscle described by De Torre,—appearances described by no other ■author. From the foregoing arguments, I think we are at full 1 liberty to conclude that De Torre, in his paper published in the Philosophical Transactions for 1755, has not described the blood < corpuscle in its natural state, and therefore that the above paper, Ifor the truth which it contains in relation to this point, may be I returned, and that without any disadvantage, to its former obli- ’vion; and when it is again produced, it may be only to please I the fancy of some laborious, but useless, book-antiquarian. In ” irelation to the observations of Martin Barry, above quoted, con- - cerning the cavity in the nucleus and of the opening in the envelope, II can only say, that I have never seen them in the blood corpus- ' cles of the chick, in any stage of their development, and I have ' examined these bodies for days and weeks together. They always appeared to me to be very decidedly convex in the centre, and tthe envelope or vesicle seemed to pass continuously over them. 2Vbte. The statements made by M. Donn^ as to the changes which the blood cor- pjwcles of mammalia present in their development, seem to agree somewhat with the observations j^t recorded. But the fnanner by which he states that these are ■produced is quite at variance with that given above; for he says that two or three](https://iiif.wellcomecollection.org/image/b21947120_0013.jp2/full/800%2C/0/default.jpg)
