Popular Science Monthly 



An Efficient Hen Is an Investment 

 Paying 150 Per Cent 



INTENT upon an increase in the egg and 

 poultry production in Texas, the de- 

 partment of poultry husbandry in the State 

 Agricultural 

 and Mechan- 

 ical College 

 has prepared 

 a photograph 

 which visual- 

 izes for the 

 farmers, and 

 the city man 

 as well, the 

 wonderful 

 earning possi- 

 bilities of the 

 hen as an in- 

 dustrial ma- 

 chine. 



Considered 

 industrially, says the department, the hen 

 is a very efficient machine. From seventy 

 pounds of feed costing about three cents 

 per pound, a good hen will produce in the 

 course of a year from 150 to 160 eggs, 

 which are worth just now about three or 

 four cents each. 



From seventy pounds of poultry food a good hen will produce 

 about one hundred and fifty eggs in the course of a year 



391 



French lines. They were notably success- 

 ful, and attracted world-wide attention. 

 Since that time numbers of trench-diggers 

 have been employed on the battlefield, 

 until now they are to be seen everywhere.. 

 In an eight-hour day one digger can 

 excavate trenches sufficient 

 to hold an army of seven 

 thousand men. It would 

 take the seven 

 t h ousand 

 troops two 

 days to dig the 

 same length of 

 trenches. Of 

 course, the dig- 

 ger makes bet^ 

 ter progress 

 where the earth 

 is free from 

 large stones and 

 obstructions. 

 The accom- 

 panying photograph shows a digger of the 

 kind generally used. Steel buckets at- 

 tached to an endless chain dig the dirt and 

 carry it up a side-chute where the dirt is 

 dumped. The matting of leaves and bran- 

 ches which covers the machine is put there 

 to deceive enemy airmen. 



An Army Burrows Itself in the 

 Ground by Machinery 



MECHANICAL trench-diggers are not 

 new, either in this country or in 

 Europe. About two years ago the first 

 machines to reach Europe were put to 

 work excavating trenches behind the 



A modern trench-digging machine excavating a 

 French soil. The machine top is decorated with 



Checking Insect Ravages with Armies 

 of Enemy Insects 



ONE hundred million dollars are lost to 

 the United States every year due to 



the ravages of insects in crops. Half these 



insects were imported. 



Though insecticides are useful, they are 

 not effective under all con- 

 ditions. The most satisfac- 

 tory results have been ob- 

 tained by introducing other 

 insects which feed upon the 

 undesirable foreign pests. 



The threatened destruc- 

 tion of California's orange 

 groves was arrested by the 

 importation from Australia 

 of a certain species of lady- 

 bird. The tiny workers were 

 shipped in tin boxes, placed 

 on ice. Once released in the 

 atmosphere of southern Cali- 

 fornia, they set about their 

 appointed duty with such 

 avidity and multiplied so 

 rapidly that the pests were 



trench on virtually wiped out in a very 



camouflage short time. 



