354 



Popular Science Monthly 



The bottles contain inks of different colors. 

 Each pen acts as a guard for its bottle 



Don't Drench a Plant: Water It 

 Drop by Drop 



LUCIEN [DANIEL, a French botanist, 

 j has discovered that young hothouse 

 plants and slips of vegetables, as well as 

 flowers, thrive far better by a system of 

 continuous watering than by drenching the 

 soil at stated periods. The new method 

 depends upon the law of capillary attrac- 

 tion. Near each plant is placed a jar con- 

 taining water, into which is dipped one 

 end of a strip of linen or cotton, whose 

 other end lies near the plant. With this 

 uninterrupted supply of water, drop by 

 drop, the plants thrived, greatly outdistan- 

 cing other plants, which were submitted to 

 an intermittent drenching. 



Using a Dozen Different Inks With- 

 out Making a Mistake 



MECHANICAL draftsmen, architects 

 and map makers often use as mani- 

 as ten inks of different colors in making a 

 complicated drawing. Sometimes it hap- 

 pens that the engrossed artist thrusts his 

 pen into the wrong bottle of ink and draws 

 a blue instead of a red line. Then follows 

 an effort to erase the wrong line, with 

 consequent loss of time. 



Frank B. Gilbreth, the well-known effi- 

 ciency engineer, overcomes this 

 difficulty very simply and ef- 

 fectively. He has devised a 

 special stand, to hold both 

 the ink bottles and their 

 pens. As the accom- 

 panying photograph 

 shows, each pen is 

 thrust vertically into 

 a hole directly in 

 front of its bottle. 

 The pens thus con- 

 stitute a barrier in 

 front of the bottles. 



When a green line 

 is to be drawn, the 

 draftsman picks up 

 the proper pen and 

 thus clears the way 

 for the green-ink bot- 

 tle; only that bot- 

 tle and no other can 

 be reached. It is 

 impossible to thrust 

 the pen into the 

 red-ink bottle, be- 

 cause that is guarded 



The Sailors and Marines Sleep On 

 Their Life-Preservers 



IT MUST afford considerable consolation 

 to the Navy recruit to realize that the 

 mattress on which he sleeps so comfortably 

 at night will stand him in good stead in 

 case of an accident to the ship. In fact the 

 very buoyancy which makes it such a 

 comfortable bed is also the quality which 

 makes it possible for it to be converted at a 

 moment's notice into a life- 

 preserver. 



The mattresses are 

 stuffed with kapok, a light- 

 er-than-cork material 

 which is imported from 

 the West Indies in bales 

 similar to bales of cot- 

 ton. It is made from 

 the seeds and silk of a 

 tree not unlike the 

 cotton-wood tree, but 

 instead of being in 

 puffy balls, the kapok 

 is in slender threads, 

 which when compressed 

 make a mass that is 

 six times more buoyant 

 than cork. 



Thin layers of the 

 kapok are enclosed in 

 strong ticking for the 

 mattresses. Each mat- 

 tress is provided with 

 tapes long enough to tie 

 around the body and 

 over the shoulders, as 

 shown in the illustration. 

 It requires only a minute 



by its pen. 



tion in their life-preserver mattresses to adjust them. 



