348 Analysis of Vol. X, Part 1. of the 
riod before the country was cleared of its original forests, when 
the inhabitants were led to cement stones by fusion, from their 
ignorance of other methods. 
4. On the Formation of Chalcedony. By Sir G. S. Macken- 
zie, Bart. F. R. S. Lond. & Ediri. — P. 82-105. 
In this paper Sir G. Mackenzie divides the different chalce- 
donies into Massive, Parallel, Botryoidal, and Pendulous. He 
considers most of these varieties as of igneous origin, and he 
conceives that the pendulous chalcedony may have been formed 
from vapour. As the greater part of this paper consists ot* the 
description of highly interesting specimens in the collection of 
the learned Baronet, it is not easy to put the reader in posses- 
sion of the curious facts which he has observed. We must, 
therefore, refer him to the memoir itself. 
5. Notice respecting the Vertebra of a Whale found in a Bed of 
bluish Clay^ near Dingwall. By Sir G. S. Mackenzie, 
F. R. S. Lond. & Edin. In a Letter to Dr Brewster, Sec. 
R. Ed. &C.--P. 105, 106. 
A brief notice of this paper has already appeared in vol. xvii. 
p. 185. of this Journal. 
6. Description of Hopeite, a New Mineral from Altenberg^ near 
AixAonChapelle. By David Brewster, LL.D. F. R. S. 
Lond. & Sec. R. S. Edin.— P. 107-111, 
This mineral was considered by the Abb^ Haiiy as a Stilbite, 
and by Mr Brooke as silicate of zinc ; but, by an examination 
of its optical characters, Dr Brewster found it to be a mineral 
entirely new, to which he gave the name of Hopeite^ in compli- 
ment to Dr Hope, the eminent Professor of Chemistry in the 
University of Edinburgh. This opinion was afterwards con- 
firmed by a crystallographic examination of the mineral by Mr 
Haidinger, and by a chemical examination of it with the blow- 
pipe by M. Nordenskjold of Abo. 
7. Astrofioniical Observations made at Paramatta a7id Sydney. 
By his Excellency Sir Thomas Brisbane, K, C. B. F.R.S. 
