Popular Science Monthly 



97 



Cleaning a Rifle Barrel by Shooting 

 a Cartridge Through It 



A MAN in Helena, Montana, has de- 

 vised a cartridge that cleans a rifle 

 barrel. He uses an ordinary lead bullet, 

 connected by a short rod with a lead plug 

 which is set against the powder charge. 

 The space between bullet and plug is 

 filled with compressed cotton, which ex- 

 pands and rubs along the bore, wiping out 

 the loose fouling. 



A very serious ob- 

 jection to this plan is 

 that the powder charge 

 is behind the cotton, 

 and deposits a new 

 load of dirt in the bore. 

 Moreover, rifles firing 

 smokeless powder can 

 not be cleaned without 

 nitrocleaners. Neither 

 the plan practical 



Rowder 



'-^"•^^m--^. 



mmfm^-/^: 



IS 



for guns shooting the 

 modern black powder. 



Compressed cotton rubs the 

 bore, wiping out the loose fouling 



goes to see the patient and to consult 

 with the physician in charge. 



After iDoth physicians have made a- 

 thorough physical examination if it seems 

 advisable, a puncture is made, to obtain 

 the spinal fluid for examination in the 

 city's research laboratories. H the pa- 

 tient is suffering from purulent menin- 

 gitis, which is meningitis due to the 

 presence of certain germs, the fluid will 

 be cloudy. In cases of tuberculous 

 meningitis, infantile 

 paralysis, pneumonia 

 and infectious diseases, 

 the fluid is clear. If 

 it is cloudy or if the 

 physician suspects that 

 the disease is a case of 

 epidemic meningitis, se- 

 rum is administered. 

 Even if the case is not 

 epidemic meningitis the 

 patient cannot be 

 harmed by the serum, 

 and if it is, a great deal 

 by prompt administra- 



What 



Spinal Fluid Tells About 

 Our Soldiers' Health 



IF one of the soldiers stationed in or near 

 New York city is taken sick and his 

 symptoms give rise to the suspicion that 

 he is suffering with meningitis, word is 

 sent at once to the Meningitis Division of 

 the Department of Health of New York 

 city. A physician from this Division 



is to be gained 

 tion of the serum. 



The number of injections vary greatly. 

 Generally not less than four must be 

 given and frequently many more are 

 necessary. The serum is never adminis- 

 tered by syringe but by gravity. The 

 spinal fluid is examined thoroughly and 

 there is no room for doubt about a 

 case when all the tests have been com- 

 pleted. 



At left: Making a culture from the spinal fluid of a soldier suspected of having meningitis. 

 At right: Making a microscopic examination at the New York Department of Health 



