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Professor Tyndall on Germs. SIS 



Summing up this portion of his inquiry, the author remarks 

 that he will hardly be charged with any desire to limit the power 

 and potency of matter. But holding the notions he does upon 

 this point, it is all the more incumbent on him to affirm that as far 



; inquiry has hitherto penetrated, life has never been proved to 



- "ir independently of antecedent life. 



ough the author had no reason to doubt the general diffusion 

 ui germs in the atmosphere, he thought it desirable to place the 

 point beyond question. At Down, Mr. Uarwin, Mr. Francis 

 Darwin ; at High Elms, Sir John Lubbock ; at Sherwood, near 

 Tunbridge Wells, Mi-. Siemens ; at Pembroke Lodge, Richmond 

 Park, Mr. Rollo Russell; at Heathfield Park, Messrs. Hamilton; 

 at Greenwich Hospital, Mr. Hirst; at Kew, Dr. Hooker; and at 

 the Crystal Palace, Mr. Price, kindly took charge of infusions, 

 every one of which became charged with organisms. To obtain 

 more definite insight regarding the diffusion of atmospheric 

 germs, a square wooden tray was pierced with 100 holes, into each 

 of w-hich was dropped a short test-tube. On Oct. 23, thirty of 

 these tubes were filled with an infusion of hay, thirty-five with an 

 infusion of turnip, and thirty-five with an infusion of beef. The 

 tubes, with their infusions, *had been previously boiled, ten at a 

 time, in an oil-bath. One hundred circles were marked on paper 

 so as to form a map of the tray, and every day the state of each 

 tube was registered upon the corresponding circle. In the follow- 

 ing description the term " cloudy " is used to denote the first stage 

 '■ ■ ' The term " muddy " is 



One tube of the 1 00 was first singled out and rendered muddy. 

 It belonged to the beef group, and it was a whole day in advance 

 of all the other tubes. The progress of putrefaction was first 

 registered on Oct, 26 ; the " map " then taken may be thus de- 



^^ Hay. — Of the thirty specimens exposed one had become 

 'muddy" — the seventh in the middle i-ow reckoning from the 

 side of the tray nearest the stove. Six tubes remained perfectly 

 clear between this muddy one and the stove, proving that 

 differences of warmth may be overridden by other causes. Every 

 ''"e of the other tubes containing the hay infusion showed spots 



very muddy, two 

 of them being in the row next the stove, one four rows distant, 

 and the remaining one seven rows away. Besides these six tubes 

 had become clouded. There was no mould on any of the tubes. 



-See/.— One tube of the thirty-five was quite muddy, in the 

 seventh row from the stove. There were three cloudy tubes, 

 While seven of them bore spots of mould. 



As a general rule organic infusions exposed to the air during 

 jhe autumn remained for two days or more perfectly clear. 

 A/oubtless from the first germs fell into them, but they required 

 time to be hatched. This "period of clearness may be called the 



penod of latency," and indeed it exactly corresponds with what 



