However,exhibitions are only useful if objects are correctly described and explained.There should be a text describing each object and its origins.In order to do this,historians and archaeologists in the museum have to do extensive research.Unless it is understood how an object relates to other object from the same period,and from earlier and later periods,it is not possible to understand the development of that object.For example,ancient glass bottles have been found all over the world.It was only through research,however,that archaeologists realized that glass blowing probably started sometime towards the end of the first century BCE.Syrian craftsmen were probably the first to use this new technology,which subsequently spread throughout Europe,and eventually to China.