Soal Latihan dan Jawaban Reading Comprehension 47
Potash (the old name for potassium carbonate) is one of the two alkalis (the other
being soda, sodium carbonate) that were used from remote antiquity in the making of
glass, and from the early Middle Ages in the making of soap: the former being the
product of heating a mixture of alkali and sand, the latter a product of alkali and
(5) vegetable oil. Their importance in the communities of colonial North America need
hardly be stressed.
Potash and soda are not interchangeable for all purposes, but for glass-or soapmaking
either would do. Soda was obtained largely from the ashes of certain
Mediterranean sea plants, potash from those of inland vegetation. Hence potash was
(10) more familiar to the early European settlers of the North American continent.
The settlement at Jamestown in Virginia was in many ways a microcosm of the
economy of colonial North America, and potash was one of its first concerns. It was
required for the glassworks, the first factory in the British colonies, and was produced
in sufficient quantity to permit the inclusion of potash in the first cargo shipped out of
(15) Jamestown. The second ship to arrive in the settlement from England included among
its passengers experts in potash making.
The method of making potash was simple enough. Logs was piled up and burned
in the open, and the ashes collected. The ashes were placed in a barrel with holes in the
bottom, and water was poured over them. The solution draining from the barrel was
(20) boiled down in iron kettles. The resulting mass was further heated to fuse the mass
into what was called potash.
In North America, potash making quickly became an adjunct to the clearing of land
for agriculture, for it was estimated that as much as half the cost of clearing land could
be recovered by the sale of potash. Some potash was exported from Maine and New
(25) Hampshire in the seventeenth century, but the market turned out to be mainly domestic,
consisting mostly of shipments from the northern to the southern colonies. For despite
the beginning of the trade at Jamestown and such encouragements as a series of acts
“to encourage the making of potash,” beginning in 1707 in South Carolina, the
softwoods in the South proved to be poor sources of the substance.
Reading Comprehension 47
How it was made
Its importance in colonial North America
Its value as a product for export
How it differs from other alkalis
They are used in making glass.
They are made from sea plants.
They are alkalis.
They are used in making soap.
making potash required less time than making soda
the colonial glassworks found soda more difficult to use
the materials needed for making soda were not readily available
potash was better than soda for making glass and soap
it helped finance the creation of farms
it could be made with a variety of materials
it could be exported to Europe in exchange for other goods
stimulated the development of new ways of glassmaking
The softwoods were not very marketable.
The softwoods were not very useful for making potash.
The softwoods were not very plentiful.
The softwoods could not be used to build houses.