514 



Journal of Agricultural Research 



Vol. IV, Nc. 6 



Table I. — Variation in transference capacity of a platinum loop when used for several 

 solutions and the variation after it had been used for a period of time "■ 



[Weight of solution transferred] 



" I gm. of distilled water at 22" C.^i c. c. 6 Average. 

 Table II. — Density of culture solutions compared with water at the same temperature 



Table III. — Experimental error when all the organisms of the loop numbering about 

 g,ooo per cubic centimeter are counted under the low power of the m.icroscope 



/ ID' 



\n{n-i) 



Probable error = ±0.6745 



= ±o.6745y^=i.92. 



= ±0.6745X1.92 = 1.29. 

 Percentage of error = 1.29-J-19.2 = 6.74. 



