No. 5. DEPARTMENT OF AGRICULTURE. 305 



After the samples of seeds have been received in the laboratory, 

 they are given a number and separately examined. The offlcial sam- 

 ples collected by special agents are received in special seed envelopes 

 and those samples which are sent in by dealers or seedsmen located 

 in the State are placed in envelopes for this purpose and properly 

 labeled and numbered. Each sample is thoroughly mixed and sub- 

 divided until the amount necessary for a test is obtained. A mix- 

 ture of seeds cannot be uniformly mixed in the same manner as can 

 material resembling flour, meal or mixed feeds, for the reason that 

 heavier and smaller seeds have a tendency to separate from the lighter 

 and larger ones, and, therefore, the portion of the sample to be tested 

 must be secured in a manner to overcome this tendency of the seeds 

 to become segregated and improperly mixed. A mixing and dividing 

 apparatus is, therefore, used to obtain the proper results. It con- 

 sists of a revolving funnel shaped hopper into which the whole sam- 

 ple is placed and by means of a set screw and disc to regulate the de- 

 livery of the seed, by revolving the hopper with the rotating crank, 

 the sample is thoroughly and accurately mixed and delivered equally 

 divided through V shaped delivery tubes into two receptacles. In 

 this manner the sample is sub-divided until the required amount is 

 secured which varies with the size and weight of the seeds under ex- 

 amination from 1 to oO grams. This amount is carefully weighed 

 on an analytical balance, all weights being recorded to the fourth 

 decimal part of a gram. 



The weighed portion of the .sample is then separated into pure seed, 

 foreign seed and inert matter by the aid of the eye or lenses and oc- 

 casionally assisted by means of various sized sieves, as the case de- 

 mands. In the case of small seeds where light chaffy material is 

 present, and especially in the case of grasses, which contain chaff, 

 pieces of stems, leaves and other foreign material, a preliminary 

 separation is made which is effected by means of an electric blower. 

 This apparatus consists of a long glass tube, one end being bent at 

 right angles, the other end being covered by a fine meshed cloth, 

 an air blast and a receiving jar. The weighed portion of the sample 

 is placed in the glass tube resting on the cloth in one end, this end 

 being inserted in the blast pipe and the other in the receiving jar. 



The air blast is turned on the light chaffy and inert material is 

 blown over into the receiving jar, the heavier portion of the sample 

 remaining in the tube. The final separation is made by placing the 

 divided portion thus obtained on a white paper-covered table, es- 

 pecially made for this purpose, and by means of the eye and lenses 

 separated into pure seed, foreign seed and inert matter as in the 

 case of samples which do not require the preliminary air blast separa- 

 tion. These portions are weighed and the percentage of each esti- 

 mated. 



If the presence of dodder or Canada thistle is noted or suspected, 

 the complete sample is examined and the proportionate number of 

 these seeds to the whole number of seeds is estimated. 



If at any time any of the members of the Board desire information 

 along this line of work, or any other work Avhich is being done in the 

 laboratory of the Department of Agriculture, we will be only too 

 glad to give all the information which we possibly can. Our labora- 

 tory is always open for any of you gentlemen, and we shall be pleased 

 to have you call and inspect the work of testing seeds for purity. 

 20—5—1914 



