The Library of Congress

Decades after the civil war, America became a giant of the industry. Old industries such as petroleum refining, steelmaking and electric power have expanded, and many new industries were born. The railroad has expanded dramatically and even the remote areas of the country were brought into the domestic market economy.

The growth of the industry changed the American society. It creates a prosperous middle class with a wealthy businessman in a new class. It also produced a very enlarged blue color working class. The labor force that enables industrialization consists of millions of new immigrants and more immigrants from rural areas. American society has never been more diversified

Not everyone shares the economic boom of this age. Many workers are usually unemployed for at least a part of the year, and the wage at work is relatively low. This situation supported many workers and joined the union. At the same time, farmers also face difficulties due to intensified competition and price reductions of agricultural products due to increased technology and production. Due to the hardships on the farm, more young people moved to town to find better job opportunities.

Americans born in the 1840s and 1850s will experience tremendous change throughout their lives. Some of these changes arise from a thorough technical revolution. For example, those primary light sources will change from a candle to a kerosene lamp and into a light bulb. They will see the traffic from walking and horsepower to steam locomotives, electric trolleys, and gasoline cars. They were born into a society where the majority of people are engaged in agriculture, experienced the industrial revolution, fundamentally changed the way people work and live the millions of people. They will experience millions of people moving from the American countryside to the country's fast-growing city.

After the establishment of the Congressional library in the mid-nineteenth century experienced the period of decline, the rapid growth of size and importance after the start of the American Civil War in the Library of Congress ultimately resulted in buildings of separate transfer copyright libraries Build and ownership in the library in all cases. Floppy disk drives have been replaced by data storage methods with large capacity such as USB flash drives, especially for traditional industrial computer equipment, are still used in some limited While you are 0 floppy disk storage capacity, portable external hard drive, CD, memory card and computer network. 0

Congress Library (LOC) - the oldest Federal Cultural Organization in the United States, research institutes, Congress and the world's largest library. It is also home to the US Copyright Office. The Library of Congress publishes its collections and posts parliamentary parliament (LOC) and uses library

Most university libraries use the US Congress library classification system to organize their books and other resources. The Library of the Congress Classification System Library collection is divided into 21 classes or categories. Each class has a specific letter assigned to it. By more detailed department, it is done by a combination of two and three letters. Corresponding character combination of library materials has the combination of the letter numbers of the US Congress library on the shelves of the university library and the US Congress library. This is often referred to as the physical number on the shelf in the library indicated with telephone number, catalog record

There is only one name authorization file in the US library. Congressional libraries are responsible for maintaining them. The authority of many subjects including the subject heading of Congress library's heading (for most academic libraries), the headings of Sears topic (for most public libraries), the medical subject headline (maintained by the National Medical Library and used in medicine) There is a document. Library etc) The catalog record you find back to where you can not see it will identify the topic permission file it uses. Like the name permission file, the subject permission record contains cross-references, so you can find the topic title you need, even if it is not completely correct. But whichever you write an authoritative record, you will expect what you are looking for.