OCTOBEE 5, 1900.] 



SCIENCE. 



529 



general which have approved themselves to 

 him during his long experience. As the author 

 franlily admits, this is not a complete worli 

 for beginners, as all theory of construction is 

 omitted ; but as an adjunct to existing text- 

 boolis it must prove of great service, being es- 

 pecially rich in examples of conventional rep- 

 resentation and of line shading. Incidentally 

 it shows also the remarkable adaptability of 

 the author's system of lettering to reduction by 

 photo-processes. 



F. N. "WiLLSON. 



Peinceton" Univeesity. 



BOOKS EECEIVED. 



Elements of 3Iineralogy, Crystallograpliy and Blowpipe 



Analysis. Alfeed J. MosES and C. L. Paesons. 



New York, D. Van Nostrand Company. 1900. 



Pp. Tii -f 409. 

 Elements of Physics for Use in High Schools. Henby 



Ceew. New York, The Maomillan Company. 



1900. Second Edition Eevised. Pp. xvi + 353. 



$1.10. 

 Ethnology. Michael Habeelandt. Translated by 



J. H. Loew, London, Dent. Pp. viii -f 169. 



SSCIENTIFIC JOURNALS AND ABTICLES. 

 The American Journal of Physiology for 

 October contains a very interesting and sug- 

 gestive article by D. J. Lingle on ' The Action 

 of certain Ions on Ventricular Muscle.' Par- 

 ticular attention is paid to the rhythmic activity 

 of heart tissue as an ion effect. Strips from the 

 ventricle of the turtle's heart were placed 

 in solutions of non-conductors, in solutions of 

 sodium, of calcium, and of potassium, and in 

 solutions of these salts combined. Lingle 

 found that the non-conductors he used (cane 

 sugar, dextrose, glycerine) did not occasion 

 rhythmic beats in the heart strips. In the 

 solution of sodium salts, however, the strips 

 always beat rhythmically. If a strip is kept in 

 the solution the beats reach a maximum and 

 then gradually decline to a complete standstill. 

 The stopping is apparently due to poisonous 

 action of the sodium salt alone, for the rhythm 

 is prolonged by diluting the solution in which 

 the strip remains or by exposing the strip for a 

 shorter interval to the action of the strong 

 solution. When transferred to solutions of 

 sodium salts, strips which have been quiescent 



in non-conductors begin to beat as suddenly as 

 if started by an electric shock. The applica- 

 tion of calcium salts and the treatment of the 

 tissue so that an excess of calcium salts remains 

 in the tissue both fail to start rhythmic beats. 

 Potassium salts are likewise ineffective. More- 

 over calcium and potassium in combination do 

 not start beats, while sodium chloride always 

 succeeds. These results have a remarkable 

 similarity to the lesults obtained by Loeb on 

 rhythmic contractions in striped muscle and the 

 tissue of the swimming bell. According to 

 Lingle, sodium and not calcium is the stimu- 

 lus for rhythmic contraction in the heart ; 

 calcium and possibly potassium salts im- 

 prove the rhythm by neutralizing the in- 

 jurious action of pure sodium salt solutions. 

 W. T. Porter and H. G. Beyer in a paper on 

 ' The Relation of the Depressor Nerve to the 

 Vasomotor Center ' raise the question, Does 

 the bulbar vasomotor center act as a physio- 

 logical unit to lower or raise the general 

 blood-pressure, or has it parts regulating the 

 regional distribution of blood? This question 

 they have endeavored to answer by investiga- 

 ting the depressor nerve, an afferent nerve 

 regarded by Cyon and Ludwig as stimulating 

 the bulbar vasomotor center to cause especial 

 dilatation of abdominal blood vessels. First 

 the depressor nerve was stimulated when the 

 splanchnic nerves were prepared for experi- 

 mentation but still intact. This caused a fall 

 in blood-pressure usually from 35 to 40 per 

 cent. Next the abdominal vessels were re- 

 moved from vasomotor influence by cutting the 

 splanchnic nerves. The blood-pressure which 

 falls on cutting these nerves was restored to 

 the normal level either by stimulating the 

 peripheral ends of the cut nerves, or by intra- 

 venous injection of normal salt solution. Now, 

 with the abdominal vessels free from vaso- 

 motor influence and the blood-pressure normal, 

 the depressor nerves were again stimulated. 

 The blood-pressure fell usually as much as it 

 had previously fallen when the abdominal ves- 

 sels were still connected with the bulb. From 

 their results the investigators conclude that 

 the depressor nerve has no special connection 

 with cells controlling vasomotor fibers of the 

 splanchnic nerves, and they express the opin- 



