1878.J the Life-History of a Minute Septic Organism. 345 



When the fluid containing the organism was inserted, a large number 

 of the organisms was seen by the lens in the cell C. The whole 

 apparatus was now placed in a copper vessel with cold water, the 

 water just covering the bulb A, and a thermometer was placed in the 

 water. A Bunsen's burner was used for heating, which had minute 

 jets springing from a tube bent in the form of a parallelogram, corre- 

 sponding to the form of the vessel. The heat was now applied, so 

 that the water rose in temperature with extreme slowness. It was 

 taken out directly the thermometer read 100° F., and at once examined. 

 Several of the organisms were at once visible : but the great majority 

 of them were quite still, and the only movement discoverable was a 

 more or less languid movement of flagella, the bodies being motion- 

 less. In seven minutes a form sailed slowly across the field, but I 

 preferred to keep my attention fixed on those which I had seen from 

 the first. In the course of three-quarters of an hour the flagella of ten 

 forms were all vigorously working, and the bodies began to move, and 

 in an hour and a-half from the time of being taken out, the whole field 

 was as active as before heating. 



In the same manner the fluid was next raised to 130° F. On exami- 

 nation the immediate effect was more marked, the inaction more com- 

 plete. Only one flagellum was seen to move in the whole field. But 

 in the course of half an hour the flagella were gently swaying, and in 

 two hours the same individuals were swimming freely. 



When, however, the fluid was raised to 140° F., the inaction was 

 absolute when the cell was first examined, and only one-fourth of the 

 individuals in a selected field revived. These did so in the course of 

 three hours, but the remainder did not move to the end of the day, 

 and were in the same position and inactive on the morrow ; and it was 

 subsequently shown, by the same means, that a temperature of 142° F. 

 was entirely destructive of the vitality of the adult. 



The next step was to ascertain the effect of the boiling point upon 

 the spores. 



To be quite sure that spores, in the condition required, were in the 

 fluid, a thin circle of glass was cut that would lie upon and take the 

 place of the ordinary floor of the " continuous stage," By this means 

 if a deposit of spores were seen to take place, it could be readily re- 

 moved bodily from the microscope. On the under surface of this circle 

 of glass a few lines with the diamond were made, in convenient places, 

 to facilitate its subsequent fracture. On this then, in the stage, pro- 

 perly covered as usual, the fluid was hunted and watched, and fresh 

 drops taken until a cyst was seen, and then watched until it burst. 

 The circle of glass on which this happened was now taken carefully 

 away from the microscope and broken, so that the pieces containing the 

 fluid drop fell into the funnel B, fig. 26. The fluid containing the 

 organism in abundance was now poured over these down the tube and 



