THIRTY-EIGHTH ANNUAL CONVENTION 129 



The wire which fastened the cotton to the carrier became en- 

 tangled on the tip of the trocar and all that could be done in 

 this case was to remove the trocar and the wire with the cotton 

 swab attached together. This was not dangerous to the animals 

 but it had this disadvantage that by the removal of the trocar 

 and the cotton, the contraction of the muscles removed in part or 

 wholly the material for examination from the swab. Whenever 

 the above described case occurs one might be led to make an 

 incorrect bacteriological diagnosis of the swab. To obviate this 

 condition we decided to fasten the swab in a different manner, 

 namely: by the use of a slide. Fig. i shows the manner in which 

 the nickel sliding tube is passed over the bent wire which holds 

 the cotton swab in place. This improved method of fastening the 

 swab is simple and easily done and a reliable and positive way 

 to successfully extract the swab from the trocar because the slid- 

 ing tube has a very smooth surface which is conical on the end 

 which goes over the folded end of the wire. In this way all 

 possibility of the swab becoming fastened is avoided. The fol- 

 lowing illustration shows the necessary instruments for the 

 work: 



a. Trocar (Closed). 



b. Trocar (Open). 



c. Stilete. 



d. Roll of wire with Cotton Swab. 



e. Upper end of wire with cotton swab inserted and slide 

 for fastening wire in position. 



f. Bottle for preserving and shipping specimen. Note 

 how wire is cut off above cork. 



g. Nickel Plated Slide. 



Method of obtaining lung specimen from cattle! After 

 applying the twitch to the nose, an assistant holds the head up- 

 ward or a rope fastened to the twitch can be thrown over a -beam 

 or rafter and the head held upward in this manner Another 

 assistant standing on the left side of the animal holds the horns 

 and turns the neck in such a position that the trachea is exposed 

 to the operator on the right. See Fig. 2. After disinfecting 

 the skin, the trocar with stilete pointing slightly downward, is 



