Convert from erg to Btu

Unit Definition (erg)
The erg is the unit of work or energy in the CGS system, equal to the work done by a force of one dyne acting through a distance of one centimeter. Equivalently, one erg is the kinetic energy of a mass of 2 grams moving at a velocity of 1 cm/sec. This is equal to 0.1 microjoule, or about 7.375 x 10E-8 foot-pound. The name of the unit is from the Greek word ergon, work. There is no symbol; the word is spelled out in full. Adding prefixes is a problem: 1000 ergs is usually called a kiloerg, but one million ergs is a megalerg, the "l" being added to ease pronunciation.

Unit Definition (Btu)
The Btu is a unit of heat energy defined as the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit. In America the British thermal unit is sometimes called the heat unit. In defining the Btu, it is necessary to specify the temperature of the water; thus there have been several definitions over the years. However, one Btu is equal to about 251.996 (small) calories, or 0.251 996 of the (kilo-)calories counted by dieters. Using the current definition of the calorie (the IT calorie), one Btu equals approximately 778.169 foot pounds, 1.055 056 kilojoules or 0.293 071 watt hour. The symbol BThU has also been used, especially in Britain.