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ants to wander about in, and in which to place food and water. A piece 

 of cloth should cover the nest. A large sheet of glass may cover the 

 shallow box to prevent too rapid evaporation. 



The next step is to capture the ants and induce them to enter the 

 nest. A colony of ants with the queen is captured as before. The 

 queen may be distinguished by her being larger than the workers. 

 They may be brought home in a glass jar mingled with the earth of 

 their former nest. The whole mass of ants and dirt is placed on top of 

 the nest prepared as above. The ants, as this dirt dries out bury them- 

 selves deep in it. Scrape away and remove all the dirt that you can 

 from the mass from time to time. This reduction of the dirt in which 

 they are hiding leads them to look for other quarters. They will be 

 likely to discover the door left for them, at which point they will begin 

 to excavate a tunnel into the prepared nest. This tunnel finally be- 

 comes a sj'stem of tunnels and passages, making their new home. In 

 this can be studied the wonderful life of the colony, by removing the 

 black cloth. The ants must be well fed and watered. Sugar, bits of 

 meat, crumbs of bread, seeds of plants, are foods of different ants. 

 This nest may be kept going for a long time. For fuller accounts con- 

 sult Lubbock's "Ants, Bees and Wasps," International Scientific Series. 

 An excellent description of an ant's nest is on page 276, Comstock's In- 

 sect Ivife (Appleton). $2.50. 



Making Qas. 



The process of making illuminating gas may thus be illustrated: 



Into a test tube place bits of wood, shavings, or sawdust. A delivery 

 tube is fitted to this as in making oxygen. Jars for catching the gas are 

 arranged also as in the oxygen experiment. The test tube full of wood 

 is now heated and the gas coming away is caught. The first gas coming 

 off is heated air from the tube. Later, gas from the decomposing wood 

 will fill a small jar. This gas may be lighted and it will be seen to 

 burn with a blue flame. It is a mixture of gases. 



In the test tube remains carbon, the charred remains of the wood. 

 The delivery tube will be coated inside with tar. If a larger apparatus 

 be used, say an iron retort (this may be made of iron gas pipe) a greater 

 heat may be used, and coal may take the place of wood, and by this 

 means a considerable amount of gas can be obtained. 



It may now be shown how in making illuminating gas, a very large 

 retort is used; arrangements are made to separate the tar, and other 

 substances from the gases; also those gases in the mixture which inter- 

 fere with the illuminating power; that the large iron gas tank corre- 

 sponds to the jar catching the gas in the experiment. 



A visit to the gas works will now be of great interest, and the main 

 processes there carried out can be clearly understood. 



Now may be taught the lesson that when coal and wood burn the 



