460 THE BEGINNINGS OF LIFE. 



a whitish deposit as a result of this. After a few weeks 

 many bluish cloudlike masses became visible in the 

 fluid, dotted here and there with minute whitish spots, 

 but no pellicle made its appearance on the surface. 

 The flask was opened at the end of the fifteenth week, 

 no apparent change having taken place. On micro- 

 scopical examination the flakes were found to have a 

 very minutely granular composition, and the whitish 

 spots on them consisted of aggregations of minute 

 linear crystals, about arrwrr" m length. The deposit 

 was composed of amorphous particles and spherules, but 

 there was no trace of the existence of living things l . 



Experiment v. A solution of eight grains of ammonic 

 carbonate and three grains of sodic phosphate in one 

 ounce of distilled water. 



When taken from the digester the glass was not in 

 the least corroded. The tube was opened at the ex- 

 piration of eight weeks, when the vacuum was found 

 to be well preserved. There was a very small amount 

 of whitish deposit at the bottom and sides of the tube, 

 though there never had been any trace of scum on the 

 surface. When examined microscopically the deposit 

 was found to be composed of more or less rounded 

 refractive particles, imbedded in a homogeneous colour- 

 less matrix. There were also very many motionless rod- 



1 This tube was one of English glass. The quality of the solution 

 must have been altogether altered by the corrosion a great part, if 

 not the whole, of the phosphoric acid being precipitated in the form 

 of insoluble phosphate of lead. 



