It is amazing that this hoard was put away - as recently as the 19th century - and then forgotten. One would have expected people to know of it.
http://www.sportsmansguide.com/net/section/sl.aspx?s=3274&rp=section
Here’s a link to a discovery of antique firearms that ended up in some palace in Nepal. Some American was travelling and heard rumors of it. He finally asked the right people and they went to go have a look. The entire palace was used for storage - it was filled with firearms (never used Gatling guns, etc.). It took him 30 years to buy them and get them out.