88 NOTICES OF BOOKS. 



ing substanocs by observing their actions on the lower organisms." Of 

 course this involves the destruction of the germs of certain organisms 

 accompauying the contagious matter of certain diseases. It would 

 occupy too much space to enter into the details of this subject ; but the 

 apparent results of Dr. Schroeter's tests may be set forth in a very 

 few words. Heat is first considered in its effects upon such organisms 

 as Bacterium Termo, Bacillus, etc. So far as the experiments went, it 

 would appear that not even so high a temperature as boiling water is 

 necessary to destroy them. But the writer urges the importance of 

 further investigation on this point with some of the still Bacteria and 

 the Micrococcus prodi J iosa. It would c(!rtainly be a great boon to poor 

 people if boiling clothes instead of burning them would destroy all 

 contagious matter. Respecting chemical disinfectants, the writer 

 points to the fact that certain fungoid parasites affect certain plants 

 to the exclusion of their nearest allies, and that a Bacterium will thrive 

 in a given fluid, but if the minutest quantity of a foreign matter is 

 mixed with it the organism perishes. Investigations conducted with 

 these facts in view may lead to some very important discoveries of 

 agents to purify the blood or intestines of germs of infectious 

 diseases. The action of permanganate acid salts is notorious. A 

 solution to saturation of permanganate of potash or soda added to the 

 foulest fluid obtained by placing decaying meat in water speedily 

 clears it ; a sediment' is precipitated, and all evil smell dissipated. 

 Experiments with Bacteria, Mucor, and Fenicillium showed 

 very strong solutions of these salts to be necessary to effect 

 their purpose. Chlorine gas and chloride of lime are next men- 

 tioned. Scientific men differ widely in opinion as to the merits of 

 these agents as disinfectants. Dr. Schroeter found that fumigation 

 with chlorine gas to be effectual must be preceded by steaming or 

 damping in some way. Dry fumigation with this gas, he asserts, is 

 utterly useless, and more than this, it is dangerous, because men place 

 confidence in it. Finally, the effects of carbolic acid are described. 

 The vapour of carbolic acid quickly destroys all growth of mould ia 

 an apartment, but it at the same time gives off an almost unbearable 

 stink. A solution of carbolic acid in the proportion of one part to 500 

 parts of water may be regarded as strong in regard to its action ou 

 living organisms. Even in the less concentrated solution of one part 

 to 1000 of water, no organism can live, and probably the much 

 weaker solution of one to 10,000 would be sulficient to arrest de- 

 velopment. For practical purposes Dr. Schroeter regards this as the 

 best disinfecting agent. In conclusion, he adds that, although in our 

 present state of knowledge we may be justified in assuming that these 

 agents will act in the same manner upon contagious matter, their real 

 efficacy can only be proved by observing their influence on the specific 

 organisms of contagion. 



Dr. Frank records some observations on the one-sided acceleration 

 of the flowering of a catkin-like inflorescence, due to the elfect of 

 light. He gives measurements of the length of the filaments of the 

 male flowers of Salix cinerea on the north and south sides, and de- 

 scribes the relative degrees of development of the anthers. To give 

 one instance, the filaments of the stamens on the south side were 8 

 millimeters long and the anther-cells completely emptied of their 



