VOL. IX.] PHILOSOPHICAL TRANSACTIONS. 149 



There are now extant systematic treatises of anatomy, so much more complete 

 than this, (which however possesses considerable merit, and was among the best 

 at the time of its publication,) that we deem an account of it altogether un- 

 necessary. 



Microscopical Observations concerning Blood, Milk, Bones, the Brain, Spittle, and 

 Cuticula, &c. By M. Leuenhoek. N° 106, p. 121. 



The small red globules in the blood, formerly spoken of in N° 1024, are 

 heavier than the crystalline liquor in which they are carried; because, soon after 

 the blood is let out of the veins, those globules gradually subside towards the 

 bottom; and consisting of soft fluid corpuscles, many of which lie on one 

 another, they unite close together, by which conjunction the blood under its 

 surface alters its colour, and becomes dark, red, or blackish. 



The red globules of the blood I reckon to be 25,000 times smaller than a 

 grain of sand ; which perhaps will to many seem incredible : but the matter 

 being about figured bodies, it is 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 globules, when they are single, and stick within to 

 the sides of very slender glass tubes, will appear white and colourless. 



I have several times endeavoured to observe the parts of a bone ; and at first 

 I imagined I saw on the surface of the shinbone of a cow, several small veins, 

 but I have not found it since in any other bone. I thought likewise, I saw then 

 also, that the bone consisted of united globules. Afterwards I viewed the shin- 

 bone of a calf, in which I found several little holes, passing from without in- 

 wards; and I then imagined that this bone had divers small pipes going long-" 

 wise ; but 1 have since observed the tooth of a cow, and found it made up of 



vast numbers of the infected, many of whose cases he has related. Among other prophylactic mea- 

 sures to which he resorted, he particularly mentions the fumigation of the bed-chambers and apart- 

 ments with the acid vapours produced by the burning of brimstone ; directing those employed in this 

 business, to withdraw from such apartments for an hour or two, until the fumigating process should be 

 finished j lest their lungs should be injured by the irritating action of the sulphureous vapour. As 

 he escaped infection himself, although he was constantly exposed to it in visiting the sick, all f>ersons 

 were eager to know what precautions he observed on this occasion. Accordingly, at the end of tlie 

 2d book, he gives a circumstantial account of his mode of living, while this contagion lasted ; whence 

 it appears that he used a generous, but not intemperate diet ; that he banished all fear, and resisted 

 as much as possible all depression of spirits; tliat he occasionally held in his mouth, and chewed 

 cardamon seeds, elecampane-root, &c. ; that he fortified his stomach with bitters and aromatics ; and 

 lastly, that he indulged freely in die smoking of tobacco; placing upon this measure more reliance 

 as a preservative, tlian is warranted by tlie experience of succeeding observers. 



