753 



THE POPULAR SCIENCE MONTHLY. 



place sufficiently long to prove that the 

 urine had been perfectly sterilized by the 

 boiling. The flasks were then rudely shak- 

 en, so us to break the capillary ends of the 

 potash-tubes and permit the liquor potassae 

 to mingle with the slightly acid liquid. The 

 urine thus neutralized was subsequently ex- 

 posed to a constant temperature of 122 

 Fahr., which is pronounced by Dr. Bastian 

 to be specially potent as regards the gen- 

 eration of organisms. 



Ten flasks, prepared as above described 

 toward the end of last September, remained 

 perfectly sterile for more than two months. 

 There is no doubt that they would have re- 

 mained so indefinitely. 



Three retorts, moreover, similar to those 

 employed by Dr. Bastian, and provided with 

 potash-tubes, had fresh urine boiled in them 

 on the 29th of September, the retorts being 

 sealed during ebullition. Several days sub- 

 sequently, the potash-tubes were broken, 

 and the urine neutralized. Subjected for 

 more than two months to a temperature of 

 122 Fahr., they failed to show any signs 

 of life. 



The Phenomena of Hypnotism. Dr. 



Heubel, in Pfii'igei-'s Archiv, rejects Czer- 

 mak's explanation of hypnotism (see The 

 Popular Science Monthly, vol. iii., p. 618, 

 vol. iv., p. 75), as also the explanation of- 

 fered by Kircher and Preyer, and thinks 

 that all previous investigators of this phe- 

 nomenon have witnessed only its first stage 

 that which is most easily induced in ani- 

 mals of relatively high organization. Cold- 

 blooded vertebrates, such as the frog, may be 

 reduced to a state of complete immobility at 

 will ; they will remain in a constrained posi- 

 tion for hours, instead of seconds or minutes. 

 This abolition of voluntary movement and 

 of consciousness is, according to the author, 

 nothing but ordinary sleep. He holds that 

 the waking state requires for its mainte- 

 nance a continual stimulation of the higher 

 nervous centres by impressions conveyed to 

 them along the various centripetal nerve- 

 fibres. By forcing an animal to remain mo- 

 tionless for a brief interval (without inflicting 

 pain), and simultaneously excluding visual 

 and auditory sensations from its brain, we 

 suddenly deprive its nerve-centres of a large 

 proportion of their accustomed stimuli. Ac- 



cordingly, they are unable to remain awake, 

 and their functional activity is only restored 

 to them when they are roused by some im- 

 pulse from without. Having satisfied him- 

 self in a variety of ways of the correctness 

 of this explanation as applied to the phe- 

 nomena exhibited by the frog, Heubel pro- 

 ceeds to extend his results to birds and 

 mammals, and arrives at the conclusion that 

 " forced sleep " will account for all the facts 

 hitherto observed. 



Further Experiments with Pntreseible 

 Fluids. Mr. Dallinger has communicated 

 to the Royal Microscopical Society of Lon- 

 don some further results of his experiments 

 with sterile putrescible fluids. In these ex- 

 periments, an air-chamber after Tyndall's 

 plan was used, and it was tested for motes 

 by a beam of oxyhydrogen-light. The 

 germs were obtained from a maceration of 

 haddock's head that had been kept for fif- 

 teen months, and found to contain numbers 

 of the " springing and calycine monads " of 

 former papers, many of the/n in a condition 

 for emitting spores. A portion of this ma- 

 terial was evaporated at the temperature of 

 150. Dust from it was diffused through 

 the Tyndall chamber, and, after the heavier 

 particles had settled, in the course of four 

 and a half hours, ten small glass basins 

 filled with Cohn's nutritive fluid, freshly 

 prepared, were introduced, six being open 

 and four covered with glass lids. In this 

 condition they were left for twenty-four 

 hours, and then the lids were removed from 

 the four covered vessels. After four days, 

 " calycine " monads were found in all the 

 first six vessels, and, in smaller numbers, 

 the " springing " sort. Two days later the 

 four vessels were examined ; in three there 

 were no calycine monads, and very few in 

 the fourth ; all exhibited the springing 

 monads. The reason of this is probably to 

 be found in the fact that the germs of the 

 calycine monads are larger than those of 

 the springing sort, and settled down first 

 from their state of suspension in the air. 



A Solar Distillery. M. Mouchot lately 

 described, at a meeting of the Paris Acad- 

 emy of Sciences, a very convenient solar 

 alembic. The mirror is fifty centimetres in 

 diameter, and the kettle holds one litre of 



