262 QUEENSLAND AGRICULTURAL JOURNAL. [1 Ocr., 1898, 
can only reach a small height, and you must have a man to hold then 
to prevent you from descending with more force than dignity. Ther4 
happened to be here a pair of iron wheels belonging to a worn-ouk 
mowing-machine, and upon these were built the ladder shown in the illustration, 
The ironwork was made by an ordinary blacksmith, and the whole can be put 
together by any handy man. The most practical way to set about the job ia 
this: Choose a level place of sufficient size, make a line to represent your 
centre of gravity, where the weight of the man in the top falls, then a line at 
right angles to represent your shafts. Then a line the length of your ladder, 
remembering that the top must not protrude beyond the centre of gravity. A 
stick or cord the length of your ladder will enable you to get the necessary 
rake, which you can make to suit your own inclination. Your props will be 
from A to B; your ladder from C to D. The ladder must project below the 
shafts a distance equal to the diameter of the wheels. It must be set out full 
size, and then you can measure off the lengths you want, thus :— 
aN 
Line of Gravity 
Line \of Shafts. 
1B 
Axle. O 
You want two pieces of hardwood, 3 inches by 2 inches, for shafts ; two pieces, 
3 inches by 14 inch, for props; and a few lengths 14 inch by 1 inch for braces, 
You attach a stout piece of hardwood along the top of your axle by two 
clamps of iron, and then attach first your shafts, and then your props, and then 
your ladder, using bolts if possible. Ours is made so that it can be taken to 
pieces in a few minutes. 
You must brace the supports with light pieces as shown in the photograph, 
also the shafts. This makes the whole affair quite rigid Cut your shafts to 
suit yourself and trim the handle, but the longer the shaft, within convenience, 
the greater the lifting power. 
Our ladder is 20 feet long. One man can not only wheel it and work it 
easily, and reach any bough 23 feet from the ground, but by “chocking” the 
wheels he can turn the ladder down so as to run under overhanging boughs, &c. 
The man seen in the top of the ladder feels far more safe and comfortable than 
he would in an ordinary ladder. It may be much higher than this. » 
f abe cost of ours was as below, but a “bush” ladder can be rigged up 
or less :— 
Ladder (20 feet, highly finished)  ...£1 0 0 
Timber... Py = te ae © © 
Paint, two coats ... a xt a ©  @ 
Bolts and iron : oe ate on O BG 
Labour (two days) 012 0 
Of course it must not be used on inclines sideways on. A plumb-line 
from the top must always fall well between the wheels near the centre of 
axles.. If you do not grasp this elementary principle of statics, better not 
yenture your neck on this (or any other) ladder. 
