Popular Science Monthly 



65 



A Rain Alarm to Make the Hired 

 Girl Get Up and Close Windows 



OXE of the countless young 

 American geniuses for \\hom 

 is waiting the worthy task of 

 carrying out some unrealized 

 ambitions of Thomas Edison, 

 has laid clairn to national atten- 

 tion by the invention of an alarm 

 apparatus which will wake up the 

 housemaid by the loud clanging 

 of a bell when the weather 

 becomes rainy. The sixteen year 

 old Edison in question lives in 

 Minneapolis. His deed was in- 

 spired by his worried mother, 

 who complained that nobody 

 woke up in the night when it 

 rained, and that the water came 

 in at the windows and ruined 

 window curtains, rugs and other 

 household valuables. 



The boy, who is a wireless en- 

 thusiast with an inner knowledge 

 of the pranks that the electric 

 current can be made to perform, 

 got but wire, batteries, and tools, 

 confiscated several articles from 

 the kitchen, and set himself to 

 the task. 



At the base of one of the 

 gutters leading from the eaves- 

 trough he attached a <ievice for making 

 electric Contact as soon as the first few drops 

 of rain fell. This device consists of a tin 

 funnel beneath which is placed a jelly- 

 glass having two strips of spring-brass 

 attached to its sides and terminating in its 

 (enter. The strips are a.djusted so that, 

 when released, they spring together 

 and send the current from con- 

 veniently located batteries 

 surging through a bell. Crys- 

 tals of coarse salt hold the 

 springs apart. When water 

 touches the crystals they 

 dissolve. Thus contact is 

 made. Even if the salt 

 should not dissolve it will 

 be saturated sufficiently to 

 allow the current to pass. 



Wires lead from the brass 

 springs to several dr>^ cells, 

 A bell is located at the 

 head of the housemaid's bed. 



The raindrops trickle 

 down the eavestrough to 

 through the funnel and on until 

 tact is made which rings the bell. 



The first drops of rain 

 trickle down from the 

 gutter to the funnel 

 leading to the battery 

 and cause the contact 

 which rings the alarm 



"POBBE.R BLD 



The eight-hour clock designed to 

 abolish computations of time 



the gutter, 

 the con- 



An Eight-Hour Clock for the Eight- 

 Hour Day 

 HARDLY was ink on the eight-hour law 

 dry, when a California watchmaker 

 devised the "eight-hour clock" and at the 

 same time offered a plan for abolishing the 

 confusion arising from the difference in 

 time between various points on the 

 continent. The new clock has 

 but eight figures on the dial, 

 with a small square in the 

 center which shows M from 

 one in the morning until 

 eight; N for noon, and £for 

 evening, the third division. 

 The inventor makes this 

 suggestion: Inaugurate a 

 uniform time all through 

 the United States, and let 

 W^ashington, D. C, be the 

 heart of our time system. 

 The twenty-four hours of 

 the day can be divided into 

 three sets of eight hours 

 and the different divisions indicated as M, 

 N, and £, or Di, D2, and D3. This would 

 eliminate time-computations. 



