BY J. C. BRUNNICH, F.1.C. BW 
used. for the calculation of the result is not a sunple one, 
as shown on the top of the table, but by the aid of this 
nomograph correct results are obtained, without turning 
over pages and pages of tables of the tabulated works 
generally used in our factories, which tables moreover give 
the results in pounds and decimal points of pounds which 
values are not so intelligible to our farmer. A similar chart 
I constructed for the calculation of commercial butter from 
given quantities of cream. As a further instance, I will show 
here a table used for the calculation of the amount of water 
evaporated to concentrate a sugar juice of a given degree 
Brix into a syrup of certain degree Brix. The original 
table gave the amount of water evaporated in per centage 
of weight of the original juice, I extended the utility of the 
table so as to be able to find directly the gallons of water 
evaporated per 100 gallons juice. 
With the graphical aids to calculations may be included 
an ingenious little instrument, costing only a few shillings : 
the mathematical Cinderella, or Engineer's Messknecht 
(measuring or rather computing servant), so called by its 
inventor, Hofrath Prof. Max Pressler. This table of handy 
pocket size, constructed of strong card board, has on one 
side a complete table of logarithms from four to five places, 
with many other useful data and constants with reference 
to weight and measures, etc. On the other side are other 
graphical tables of reciprocals, circumference and surfaces 
of circles of various diameters, squares and cubes of numbers, 
chords, arcs, sines, cosines, tangents and secants of all 
angles. The instrument may be used, like a regular multum- 
in-parvo, for rough surveys and levelling, for the estimation 
of true sun time, the estimation of heights of trees and 
mountains, for the estimation of the cubic contents of 
standing and felled trees. To give an instance how handy 
the arrangement of these tables are for calculations, which 
otherwise would require large volumes of tables, I will give 
an example taken at ‘random from the httle pocket book, 
issued with the instrument. In a railway to be constructed, 
the line of rails has to change its direction by an angle 
of 31.4 degrees, and the lines have to be connected by a 
curve 200 yards radius (See Plate Il.) The surveyor wishes 
to know : — 
