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NEW DOSAGE TABLES 



BY C. W. WOODWORTH 



A new principle applicable to the construction of dosage tables 

 was discovered while making a careful comparison of the rate of 

 charge in the dose necessary to compensate for the differences in 

 leakage. 



Since large tents contain a greater volume of gas in proportion to 

 the surface than smaller tents the leakage is correspondingly less 

 important and it is possible to arrange a series of sizes of tents which 

 will correspond with the various degrees of leakage in such a manner 

 that they should require identical doses. 



Such a series, omitting the fraction, is as follows : 

 37 35 32 30 28 26 24 ft. 

 .10 .15 .20 .25 .30 .35 .40 % 



A further inspection brought out the fact that while these num- 

 bers do not form a regular simple series the doses that are assigned 

 to these sizes under the same tent do form a regular geometrical pro- 

 gression decreasing at such a rate that after five intervals the num- 

 ber is reduced by one half. 



The principle is then that an arithmetical series of leakages is 

 related to a geometrical series of dosages and both correspond to the 

 same complex series of sizes of tents. 



The application of this principle to the construction of dosage 

 tables resulted in the production of the remarkably simple and prac- 

 tical form presented below. It is necessary to point out again that 

 there is urgent need of a series of new and acceptable tables. 



One of the causes of the continued dissatisfaction with the process 

 of fumigating citrus trees is the common use of dosage tables that 

 are grossly inaccurate. It is difficult to understand why these should 

 be so persistently advocated unless it be that their inaccuracy has 

 not been sufficiently emphasized. 



The tables most in use are incorrect in the three following par- 

 ticulars. 



I. SHAPE 



The range of shape found in the extensive series of measurements 

 made by this station varied between tents in which the distance over 

 equaled that around the tent in the case of high seedling orange trees 

 to the low broad lemons which had a circumference twice that of the 

 distance over the top. 



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