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THE POPULAR SCIENCE MONTHLY. 



from which, like the Egyptian towns, it is 

 named, and (as the Egyptians did) it refuses 

 to eat that animal or plant. Further and 

 this is the essential point of our explanation 

 among the tribes which act thus, the 

 mother is the permanent element in the 

 family, and the children (as the Egyptians 

 did) derive their names, not from the father, 

 but from the mother's family." Among 

 most of the purest races the various stocks 

 which worship the different animals arc scat- 

 tered through all the local tribes. But in 

 China, the worshipers of each animal, or 

 at least the people who derive their name 

 from him, are gathered together, as in Egypt, 

 into local aggregates. Thus, the Egyptian 

 marriage customs and the Egyptian animal- 

 worship both seem susceptible of explana- 

 tion as relics of savagery preserved into the 

 midst of civilization by the extraordinary 

 tenacity of Egyptian conservatism. 



A Glossary of Microbes. Mr. W. Ilamlet 

 gives the following classification of the mi- 

 crobes (microscopic organisms of fermenta- 

 tion and disease): 1. Microbes which ap- 

 pear as points are called monads, monera, 

 or micrococci. They are motionless, and 

 may be regarded as the spores of other mi- 

 crobes. 2. Motionless linear microbes the 

 Bacteridians and the bacilli. To them be- 

 longs Bacillus anthracis. 3. Cylindrical mo- 

 bile microbes, having rounded ends or con- 

 tracted in the middle so as to form an 3> 

 are the bacteria proper. Among them is 

 Bacterium termo of putrefaction, the com- 

 monest of all. 4. Flexuous mobile microbes. 

 They look and act like eels, and differ but 

 little from the equally active bacteria. They 

 are the vibrios. 5. Spiral microbes, resem- 

 bling a cork-screw, and mobile ; Spirilla spi- 

 rochetCB. Their presence in human blood 

 appears to be connected with intermittent 

 fever. 6. Microbes with heads, very active, 

 having globules larger and more refractive 

 than the rest of the body at one or both 

 ends. These globules arc apparently spores 

 ready to be detached from a bacterium 

 I;, i,l, ,-iii hi ciipitatum. Besides these six 

 principal states, the microbes form agglom- 

 erations or colonics that often notably 

 change the aspect of the elementary cells, 

 and which have received various names. 

 Agglomerations in microscopic masses, sur- 



rounded by a jelly that sticks them together 

 and deprives them of motion, are called 

 zooghea. A non - gelatinous membrane 

 formed of motionless bacteria is a myco- 

 derma. Bacteria attached end to end in a 

 string form filaments of leptothrix. A num- 

 ber of spherical micrococci joined one after 

 another form the string of round grains 

 called a torula. A considerable number of 

 species may be included in each of these 

 divisions ; and there does not appear at 

 present any way to distinguish by sight a 

 disease-producing bacterium from a harm- 

 less one. 



Circulation of Blood in the Brain. Sig- 

 nor Mosso, who has been engaged on the 

 subject for six years, has published some 

 new observations on the different conditions 

 of the circulation of the blood in the brain. 

 He has had the privilege of observing three 

 patients who had holes in their skulls, per- 

 mitting the examination of the encephalic 

 movements and circulation. No part of the 

 body exhibits a pulsation as varied in its 

 form as the brain. The pulsation may be 

 described as tricuspid ; that is, it consists 

 of a strong beat, preceded and followed by 

 lesser beats. It gathers strength when the 

 brain is at work, corresponding with the 

 more rapid flow of blood to the organ. The 

 increase in the volume of the brain does not 

 depend upon any change in the respiratory 

 rhythm; for, if we take the pulse of the 

 fore-arm simultaneously with that of the 

 brain, we can not perceive that the cerebral 

 labor exercises any influence upon the fore- 

 arm, although the pulsation in the brain 

 may be considerably modified. The emo- 

 tions have a similar effect upon the circula- 

 tion of the brain to that of cerebral labor. 

 Signor Mosso has also observed and regis- 

 tered graphically the variations of the cere- 

 bral pulse during sleep. Generally the 

 pulses of the wrist and the brain vary op- 

 positely. At the moment of waking, the 

 pulse of the wrist diminishes, while that 

 of the brain increases. The cerebral pulsa- 

 tions diminish as the sleep grows deeper, 

 and at last become very weak. Outward 

 excitations determine the same modifications 

 during sleep as in the waking state, without 

 waking the sleeper. A deep inspiration 

 always produces a diminution in the volume 



