Dr. Playfair’s Lecture on the Great Exhibition of 1851. 19 
value of barn-yard products, notions, the value of which experi- 
ence has taught, and which all scientific investigations are now 
confirming, may not be underrated, or undervalued. 
ere is another topic in this connection to which I may 
be permitted to allude, as it deeply concerns the prosperity of 
scientific agriculture in this country—and that is, the tariff of 
prices paid for soil analyses. My own opinion, and the opinion of 
of others who are most conversant with this subject is, that a com- 
plete and thorough soil analysis cannot be made with any profit 
to the analyst for a less sum than twenty dollars. Yet the usual 
price charged is about one-fourth this sum, and ina comparatively 
recent instance, the editor of an agricultural paper in one of the 
northern states, has publicly offered to make complete and thorough 
soil analyses for the sum of two dollars. Such a proposition 
above mentioned rates. My excuse for introducing this subject, 
will I trust be found in its importance. 
Arr. IV.—On the Chemical Principles involved in the Manu- 
ees of the Great Exhibition; by Lyon Puiayram, C.B., 
. ao * 
Tue industrial products of the different countries represented 
at the Exhibition showed, as a marked feature of ascending civil- 
ization, that civilized states differ from barbarous nations in their 
* From the Lectures on the results of the Exhibition, delivered before the Society 
of Arts, Aigtiehnnae ak Decnanee, at the suggestion of H. R. H. Prince Albert, 
President of the Society. 
