Mar. 30, 1888] 



SCIENTIFIC NEWS. 



305 



of the lower half of the tube. This method is preferred 

 by those experimenters who employ a solid material for 

 the cultivation of micro-organisms ; whereas the method 

 of the Montsouris observers has most favour from those 

 who germinate the organisms with liquid food. 



Dr. P. F. Frankland has lately contributed an admir- 

 able critical paper on this subject to the Royal Society. 

 He objects to the process adopted by MM. Freudenreich 

 and Miquel, for several reasons. By it each individual 

 experiment is attended with great expenditure of time, 

 trouble, and material, for the water with which the glass- 

 wool plug is agitated has to be divided amongst a large 

 number (ten, thirty, forty, or more) of culture-tubes in 

 one single experiment. 



Again, as it is necessary in the process to have the 

 water with which the glass-wool plug is mixed so divided 

 that each part shall only contain one organism, it becomes 

 very tedious to dilute the water in due proportion to 

 secure this condition. For should the quantity of water 

 taken for mixing be wrongly proportioned, the experi- 

 ment would be worthless, as no calculation with regard 

 to the number of micro-organisms could be made. 



Again, the assumption that each tube suffering, altera- 

 tion does so in consequence of the introduction of a single 

 organism must be accepted with much reserve, more 

 especially as the difficulty of equally distributing the 

 organisms in the water, however carefully and regularly 

 shaken, is rendered almost insurmountable through the 

 presence of the suspended particles of glass-wool. 



Dr. Frankland has for a time been adopting Hesse's 

 method for carrying out a number of experiments on the 

 distribution of micro-organisms in air. The method 

 possesses the great advantage that the tubes, afcer pre- 

 paration in the laborator}', can be carried to the place 

 where the experiment is to be performed, and that there 

 are no further operations requiring special appliances. 

 Special precautions, however, are needed in hot weather, 

 when the experiments are made in direct sunshine, to 

 prevent the melting of the gelatine film. He found, too, 

 that the number of organisms deposited in the tube was 

 greater when pointing towards the wind than when 

 pointing away from the wind. In consequence he 

 directed the open end of the tube at an angle of 45° 

 above the horizontal towards the wind. In this way the 

 wind does not blow down the tube. But he has latterly 

 exposed, side by side with the tube through which the air 

 was aspirated, a second similar tube by way of control, 

 and he has ascertained that the number of colonies 

 making their appearance m the control-tube frequently 

 amounted to a large fraction of the number found in the 

 tube through which the air had been aspirated. 



— •-;>6^^:'^ — 



LITTLE THINGS THAT KILL. 



AT various times the newspapers have warned the 

 public against swallowing the seeds of grapes, 

 oranges, etc., because of the danger of such substances 

 getting into a small intestinal bag, or cul-de-sac, called by 

 doctors the appendix vermiformis. This is a receptacle 

 formed at the junction of the large and small intestines, 

 but its use or object no physician knows. It has been 

 thought to be a rudimentary or incomplete formation, or 

 possibly some meaningless survival of a lost anterior 

 type. At any rate, its existence, while presenting no 

 apparent " reason for being," as the French say, is, on 

 the other hand, a positive and constant source of danger. 



because of the liability of its becoming the receptacle of 

 some undigested seed or other indigestible substance. 

 In that case it produces a state of inflammation, which, 

 in nearly all cases, proves fatal. Fortunately but few 

 seeds among the great number so heedlessly swallowed 

 seem to get into this little death-trap, although any one 

 seems likely to lodge. Perhaps more cases of inflam- 

 mation of the bovv'els than the doctors suspect may be, 

 in reality, due to this obscure and disregarded cause. 



— «-^>t^»^»tf=-» — 



WASTE. 



THE complete erasure of the word " waste " from the 

 dictionaries — at all events, in so fir as it has any 

 relation to industrial products — is, if not quite an accom- 

 plished fact, imdoubtedly becoming more and more 

 imminent ; and we may thank the chemists of this 

 generation for teaching us how to recover and utilize 

 innumerable substances which, in their ignorance, our 

 grandfathers threw away. Thirty years ago the manu- 

 facturers of iron, gas, and chemicals everywhere 

 neglected all but the prime objects of their industries, 

 whereas to-day, on the system of taking care of the 

 pennies and allowing the pounds to take care of them- 

 selves, competition has induced us to regard our 

 legionary by-products as so many integral parts or 

 branches of each enterprise. If the intelligent men who 

 have "gone before," and who were looked upon by 

 their contemporaries as wise in their generation, could 

 by any chance reappear among us, we might conduct 

 them to our gasworks, and, with a certain pride, explain 

 the origin of our sulphate of ammonia, our aniline dj'es, 

 and our hundred other extracts from coal tar. From 

 the contemplation of gas we would turn with them to 

 some of our smelters and furnaces, and point to the 

 mineral wool, the cement, the glassware, the pottery, 

 the fire bricks, and the fertilizer, all derived from our 

 furnace slag; and finally, entering a great chemical 

 works, we should show them how the once devastating 

 gases, so fatal to life and vegetation, are no longer sent 

 free into the air, but are condensed and transformed 

 into staple articles of trade ; and how by an ingenious, 

 and, to them, undreamed of process we extract the 

 precious metals from our exhausted sulphur ores. lo 

 their wondering question, " How can these things be ? " 

 we might reply that all these marvels recult from a 

 modern and enlightened policy, which, in many countries, 

 has fostered every species of research in every branch 

 of science, encouraged great minds to ponder over and 

 gradually unravel the mysteries of nature, and stimu- 

 lated a general thirsting for that knowledge which, 

 properly applied, must ever ameliorate our condition in 

 this " vale of tears." — The Age of Steel. 



The Death-rate in Great Cities.— The Bulletin 

 Medical gives the following as the death-rate of thirty 

 great cities, excluding London : — Brussels, 15 per 1,000; 

 Amsterdam, the Hague, and Philadelphia, 16; Stockholm 

 and Baltimore, 17 ; Dresden, iS ; Vienna and Turin, 19 ; 

 Berlin, New York, and Brooklyn, 20; Paris, 21 ; Christi- 

 ania, 22 ; St. Petersburg, 23 ; Venice, 24 ; Budapest, 

 Bombay, and Calcutta, 25 ; Rotterdam, Breslau, and 

 Prague, 26; Munich, 27; Hamburg, 29; Trieste, 30; 

 Copenhagen, 31 ; Alexandria, 35 ; Rome, 37 ; Madras, 43 

 and Cairo, 51, 



