Louis Pasteur. In 1881-1885 Louis Pasteur first used animals as model for growing and studying viruses. He found that the rabies virus could be cultured in rabbit brains and discovered the rabies vaccine. However, Pasteur did not try to identify the infectious agent. The discovery of viruses. 1886-1903 â This period was the discovery period where the viruses were actually found. Ivanowski observed/looked for bacteria like substance and in 1898, Beijerink demonstrated filterable characteristic of the virus and found that the virus is an obligate parasite. This means that the virus is unable to live on its own.
The present gold holdings at the Fort Knox Gold Bullion Depository amount to approximately 147.3 million ounces worth more than 6 Trillion Dollars! Except for small samples removed to test its purity, no gold has been transferred to or from the Depository for many years.
One of the first written accounts questioning the amount of gold really stored in Fort Knox appeared in 1974 in a tabloid, the National Tattler. An unnamed informant claimed that there was no gold left in Fort Knox.