grandfatherstreaure

Typewriters

2008-07-18T04:13:00.000-07:00

A typewriter is a mechanical or electromechanical device with a set of "keys" that, when pressed, cause characters to be printed on a medium, usually paper. For much of the 20th century, typewriters were indispensable tools in business offices and for many professional writers. By the end of the 1980s, word processor applications on personal computers had largely replaced the tasks previously accomplished with typewriters. Typewriters, however, remain popular in the developing world and among some niche markets.[citation needed]

By the mid-1800s, the increasing pace of business communication was creating a need for mechanization of the writing process. Stenographers and telegraphers could take down information at rates up to 130 words per minute, but a writer with a pen was limited to about 30 words per minute (the 1853 speed record).[4] From 1829 to 1870, many printing or typing machines were patented by inventors in Europe and America, but none went into commercial production.
Many old typewriters do not contain a separate key for the numeral 1 or the exclamation point, and some even older ones also lack the numeral zero. Typists who learned on these machines learned the habit of using the lowercase letter l for the digit 1, and the uppercase O for the zero. The exclamation point was a three-stroke combination of an apostrophe, a backspace, and a period. These characters were omitted to simplify design and reduce manufacturing and maintenance costs; they were chosen specifically because they were "redundant" and could be recreated using other keys. On modern keyboards, the exclamation point is the shifted character on the 1 key, a direct result of the heritage that these were the last characters to become "standard" on keyboards.

Stone grinder

2008-07-18T04:08:00.001-07:00

A mortar and pestle is a tool used to crush, grind, and mix substances. The pestle is a heavy stick whose end is used for pounding and grinding, and the mortar is a bowl. The substance is ground between the pestle and the mortar. The antiquity of these tools is well documented in some early literature, such as the Egyptian "Papyrus Ebers" of c. 1550 B.C.E. (the oldest preserved medical literature piece) and the Old Testament (Numbers 11:8 and Proverbs 27:22).[2]
Medical use
Mortars and pestles were traditionally used in pharmacies to crush various ingredients prior to preparing an extemporaneous prescription. The mortar and pestle is the most common icon associated with pharmacies. For pharmaceutical use, the mortar and the head of the pestle are usually made of porcelain, while the handle of the pestle is made of wood. This is known as a Wedgwood mortar and pestle and originated in 1779.
Food preparation
Mortars are also used in cooking to prepare ingredients such as guacamole and pesto (which derives its name from the pestle pounding), as well as grinding spices into powder. Native American tribes used mortars carved into the bedrock to grind acorns and other nuts. Granite mortars and pestles are used in Southeast Asia and India. In Malay, it is known as lesung. Traditional Mexican mortar and pestles, made of basalt, are known as molcajetes.

Food preparation

Sewing Machine

2008-07-18T04:04:00.001-07:00

A sewing machine is a textile machine used to stitch fabric or other material together with thread. Sewing machines were invented during the first Industrial Revolution with the intention of decreasing the amount of manual sewing work performed in cloth companies. Since the invention of the first working sewing machine, generally considered to have been the work of Englishman Thomas Saint in 1790,[1] the sewing machine has vastly improved the efficiency and productivity of fabric and clothing industries.

Though some older machines use a chain stitch, the basic stitch of a modern sewing machine consists of two threads and is known as lockstitch, Modern sewing machines are designed in such a way that the fabric easily glides in and out of the machine without the hassle of needles and thimbles and other such tools used in hand sewing, automating the process of stitching and saving time.

Gramophone(:

2008-07-18T03:50:00.001-07:00

Early attempts to design a consumer sound or music playing gadget began in 1877 when Thomas Edison invented his tin-foil phonograph. The word "phonograph" was Edison's trade name for his device, which played recorded sounds from round cylinders. The sound quality on the phonograph was bad and each recording lasted for one only play. Edison's phonograph was followed by Alexander Graham Bell's graphophone. The graphophone used wax cylinders which could be played many times, however, each cylinder had to be recorded separately making the mass reproduction of the same music or sounds impossible with the graphophone.
On November 8 1887, Emile Berliner, a German immigrant working in Washington D.C., patented a successful system of sound recording. Berliner was the first inventor to stop recording on cylinders and start recording on flat disks or records.
The first records were made of glass, later zinc, and eventually plastic. A spiral groove with sound information was etched into the flat record. The record was rotated on the gramophone. The "arm" of the gramophone held a needle that read the grooves in the record by vibration and transmitting the information to the gramophone speaker.(See larger view of gramophone)
Berliner's disks (records) were the first sound recordings that could be mass-produced by creating master recordings from which molds were made. From each mold, hundreds of disks were pressed.