
          Smithsonian Instution
May 10th 1859

My Dear Dr

Your letter of the 4th inst was
duly received and was immediately
referred to the principal
mathematical assistant of the
coast survey who in the absence
of Mr [Buche?] has furnished the
enclosed answer to your enquiries
which I hope will be sufficient
for your purpose.

I return the number of the
Journal of Gas Lighting from
which it appears that the subject
of gas measurement is one which
is awakening much attention.

The whole subject of the manufactory
and use of gas is increasing
        