866 
Sux>plemerit to the “ Tropical Agricidturist: 
[June 1, 1898. 
THE USES OP WOOD. 
(^Continued.) 
8. Wood is a poor conductor of heat and 
electricity, Heated to 150° P. or cooled below the 
freezing point of water, iron, steel, rmd other 
metals are painful to the touch, and even far 
within these limits metal objects are objection- 
able on account of their ready conductivity of 
heat. Wood, on the other hand, is entirely in- 
offensive as long as its temperature remains with- 
in the above limits. The objections to metal 
dwellings on this account are experienced also in 
heavy-armoured ships, which, in spite of the excel- 
lence of an oceanic climate, are notoriously uncom- 
fortable and even injurious to health. 
When exposed to heat, wood is ignited and 
destroyed by fire. The inflammability and com- 
bustibility of vvoed at high temperatures, though 
among its most valuable properties, are, at time.s, 
a drawback which metals do not share; neverthe- 
less, during conflagrations the behaviour of wooden 
structures; for, while abeam of wood burns, it 
retains its shape to the last, and the structure 
may stand and be saved, w'hile under the same 
circumstances metal beams twist out of shape and 
thereby occasion the fall of the entire structure. 
This behaviour of wood in conflagration has induced 
the best authorities, fire underwriters and others 
to recommend the use of iwood iti all large struc- 
tures where tlie combustible contents of the 
rooms' annul the value of fireproof metal con- 
struction. 
If w'ood were a good conductor of electricity, 
its usefulness as a material of construction in our 
large cities would be much impaired, for it 
ii])pears to be a very serious and constantly grow- 
ing difficulty to protect life and property against 
this dangerous and yet so useful force. 
' 9. Woods are normally inoffensive in smell 
and taste ; liquor.s and wines of the most delicate 
flavours are kept in oaken casks for immy years 
without suffering in quality. Cliemical changes, 
often directly producing poison, prevent the use 
of cheap metals for these purposes. 
10. Owing to their structure, all woods present 
varieties of characteristic aspects and posse.ss no 
small degree of beauty. A plain surface of metal, 
of whatever kind, is monotonous, while one of 
wood, unless marred by paint, presents .such a 
variety of unobtrusive figure.s tiiat the eye never 
tires of seeing them. That this beauty is quite 
fully appreciated is best illustrated by the fact 
that pianos, sideboards, and other elegant furni- 
ture are not covered wiih slieet. metal (as they 
might very cheajily and iffeclively be), aud that 
the handsome floors of costly structures are 
neither painted nor car[)eted. 
11. Wcod is easily and effectively united by 
the sim])le process of gluing, so that valuable 
combinations, whether for beliaviour, strength, or 
beauty, are posi-ible. A three-ply veneer board 
may not only' he us jiretiy as, but also more 
serviceable than, a simple board of any one of 
the two or three kinds of wood of which it is 
composed, and a white-])ine dcor with cherry or 
walnut veneer is not only fully as handsome as a 
walnut door, but it is far superior in its behaviour. 
Since all shrinking and wasping i,s thereby prac- 
tically prevented, iron and steel may be 
welded, most metals can be soldered, but none 
of these processes can be compared to gluing in 
effectiveness and ease of ojjeration. 
So far wood has been regarded only as a 
material of construction ; but while this is perhaps 
the most important consideration, the u.'^e of 
wmod is a substance which may be altered physi- 
cnlly' aud chemically- is far more important than 
is generally admitted. 
12. The great mass of mankind is w-armed and 
has its food cooked by wood fires. Even in this 
country' today', in .cpite of the great competition of 
coal, three-fourths of all the houses and thousands 
of manufacturing establishments are supplied 
with heat from wood. 
13. Wood is ground into pulp and made into 
paper and pulp boards with endless variety- of 
application. Wood pulp made by- chemical pro- 
cesses, results ill cellulose and its countless deri- 
vatives, which are capable of supplying almost 
anything, from a shirt collar to a car wheel. 
CONDENSED MILK. 
Fifteen thousand cows are required to produce 
the condensed milk of Switzerland. During recent 
years the condensed milk industry collectively, 
the new competitors do not approach the output 
of the pioneer country. 
There are a great many conden.«ed milk factories 
in Sw'itzerland, most of which have sprung into 
life during the last five or six years, until Swiss 
milk brands in a shop window now present almost 
as bewildering a variety as the Swedish matches, 
The industry mainly depends, howevei’, upon three 
large factories. The Henri Nestle Company, with 
its three works at Veney', Bercher and Payerene ; 
the Anglo-Swiss Company-, with factories at Cham 
and Guin ; and the works of Lapp, at Epaquy, 
Henri Nestle, who, like so many modem captains 
of industry, started life as a pharmacist, was the 
pioneer of the condensed mi^t busine.'S. His 
invention proved a gold mine, and at his death, 
a year or two ago, he was reckoned one of the 
wealthiest citizens of the Republic. . 
The Pbocess is Simple, 
The proces.s of the condensed milk manufacture 
is exceedingly simple. Almost every village ia 
the district tapped by' one of the factorie.s, pos- 
sesses a milk-ccllecting office, to which the pea- 
sants briiig the milk fresh from the cow. The 
milk offices are owned by separate companies, 
with whom the factories contract for their supplies. 
At the collecting office the milk undergoes a refri- 
gerating proces.s. Upon its arrival at the factory 
it is first warmed gently over a vapour bath and 
then exposed to a greater heat (not, however, 
exceeding 176° Fuhr.) in copper vessels, The next 
manipulation consists in the addition to the milk 
of 13 per cent by weight of the best reined sugar. 
The mixture is then pumped into a vacuum pau 
for condensation. There is nothing special about 
these vacuum pans. They are the kind u.sed at 
almost every manufacturing chemist's, in sugar 
factories and in many other works, 
What Good Condensed Milk should Contaik. 
The pans have a false bottom, and are fitted 
with spiral hotwater tabes. The aqueous vapours 
