Page:Popular Science Monthly Volume 89.djvu/244

 �Popular Science MoyitJdy

��The adaptable stepladder in two of many posi- tions in which it may be placed. On the left, the bracing legs are folded up on a bench and the stepped legs reach to the floor. On the right, the position is exactly reversed, with stepped legs folded up and bracing legs in extended position

���A Stepladder with an Ambition to Adapt Itself

THE common or garden variety of stepladder has been in use for so many years that most inventors have forgotten about the possibility of im- ])rovements. An Oregonian who had some tasks of varying lieight to accom- plish, hit upon an ingenious idea in adapt- able stepladdcrs and secured a patent. In appearance, when folded, the ladder could almost be classed as "pocket va- riety." It is not much longer than a man's arm, yet when it is unliingcd it aitains a height of about five feet. The most ingenious feature of its construc- tion is the provision of foreshortened legs. The legs which are fitted with steps are placed upon a stool or a chair of ordinary Iieiglit. The bracing legs reach to the (loor. This performance is reversible: i. e., the bracing legs can be folded up and jilaced upon a ciiair with the slep[)ed legs resting on the tloor. Also, both sections can be opened, wlieii the ladder becomes an ordinary stej)- ladder. In its extended position it

��looks fragile and too light to sustain a heavy weight, but it can hold up a li\e weight of two hundred pounds and more in any one of the several positions in which it may be placed. As a service- able, portable ladder around the home it meets every requirement.

��Pulverized- Coal Burners on Our Modern Steamships

THE combustion of a "spray" of coal- dust blown into the fire-box ,by a blast of air is very nearly jicrfcct, eliminating smoke, cinders, and firing tools. A high temi^erature is obtained, actually melting the ash which runs down tile walls of the fire-box, and which is easily disiioscd of. The use ol this de- vice, so similar to oil-burners where a jet of oil is blown in the boiler with a stream of air or steam, is past the ex- perimental stage. More heat is obtained iroin a ton <if coal in this way; and rather tests succcetl, that coal-dust burners may displace oil-burners on many steamships.
 * )oor coal can be used. It is jirobable, if

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