400 Heidelberg Collectionof Rocks and Petrifactions: 
advantage, both for study and instruction, peirifactions must 
orm a part. 
This want, so severely felt by every friend of geology, we 
propose to relieve, by furnishing Collections of Rocks and 
Petrifactions, in complete and characteristic specimens, not 
surpassed for excellence in their kind. 
For the accommodation of our respected correspondents, 
they shall be furnished within the term of six months and at 
the lowest freight. Each of these parcels, sent at any one 
time, shall consist of from 50 to 60 specimens, both of rocks 
and petrifactions; the first of the size of 12 square inches, the 
whole selected in the best manner, omitting superfluous du- 
plicates and uninteresting varieties. 
Every specimen shall be furnished with a label indicating 
the systematic nomenclature, in German, in French, and in 
English, and the locality besides. Every parcel shall con- 
tain, as far as possible, specimens of all the principal varieties 
of petrifactions ; so that those to whom they are sent, may im- 
i arrange them according to the most approved geolo- 
gical systems of ‘ Humboldt,” “ Boué,” &c. Finally, towards 
the conclusion of a delivering,* there shall be furnished a 
catalogue raisonnée to the whole, which shall be furnished 
within 8 to 10 of the above said terms. In relation to this 
of next June, (1927) and the ription will not close before 
that time. The price of each parcel sent is (illegible, Ed.) 
and for this amount, for the convenience of the subscribers, 
we shall draw on them at two months from the date of the in- 
voice. We profit by this opportunity to recommend our insti- 
tute to the favor of the public. We have always on hand a 
- great choice of minerals, in single specimens, as well as in 
systematical collections, at the lowest rate, and catalogues of 
our minerals are furnished gratis. 
Heidelberg, Dec. 1, 1826. 
__ * his is the word in the original paper, meaning what in French would 
he called envoi, viz—the things sent and the act of sending at any particular 
 fime. We have ingle English word that exactly expresses the idea —Er 
