Double Eagle in the first transatlantic balloon, was greeted by avid crowds in France.

By the nineteenth century, embroidery on men's clothing had virtually disappeared except for the occasional decorative vest and tie.

The Salk vaccine is a major factor in the fight to eradicate polio.

Comets are still regarded with awe by some people.

The economy of Dallas, Texas, is strong and diversified .

Although the Carbon 14 method of dating old objects is not foolproof , it is the best method available at present

People who do not sleep enough tend to become irritable .

One of the greatest breakthroughs for professional women came in 1973 when the field of banking opened up for them.

Solid geometry has enabled astronomers to calculate the positions of the heavenly bodies relative to one another.

Cream of tartar 酒石 , a weak acid, can be added to egg whites to help them foam泡沫 when they are beaten