78 Miscellaneous. 



period through which vegetative powers can be preserved ; 

 yet as many accounts are recorded of seeds vegetating spon- 

 taneously in such soils, it would be well to set these state- 

 ments at rest by actual experiment. 

 In such experiments, state the formation, and describe the geolo- 

 gical phenomena of the locality, together with the depth from the 

 present surface at which the soil was obtained. 



b. Natural deposits of the recent period may be classed as fol- 

 lows : — 



Alluvions of rivers. 



Tidal warp land. 



Shell marl. 



Peat. 



Surface-soil buried by landslips. 



Ditto ditto by volcanic eruptions. 

 In these cases, state the nature of the soil, the depth from the sur- 

 face, &c. ; and especially endeavour to obtain an approximate date 

 to each specimen of soil, by comparing its depth from the surface 

 with the present rate of deposition, or by consulting historical re- 

 cords. It would be well to submit to experiment a series of samples 

 of soil taken from successive depths at the same locality. 



c. Artificial deposits are as follows : — 



Ancient tumuli. 

 Ancient encampments. 



The soil beneath the foundation of buildings. 

 The soil with which graves, wells, mines, or other excava- 

 tions have been filled up. 

 Ridges of arable land, &c. 

 In these cases, state, as before, the depth from the surface, and 

 ascertain from historical sources the approximate age of the deposit. 

 2. By trying experiments on actual seeds which exist in artificial 

 repositories. These are, — 



Seeds in old herbaria and botanical museums. 



Seeds obtained from mummies, funereal urns, at Pompeii, 



Herculaneum, &c. 

 Dated samples of old seeds from nurserymen and seedsmen. 

 In these cases, state the circumstances in which the seeds have 

 been preserved, and their date as nearly as it can be ascertained. 



B. Prospective Experiments. 

 In this department of the inquiry, it is proposed to form de- 

 posits of various kinds of seeds under different conditions, and to 

 place a portion of them at successive periods under circumstances 

 calculated to excite the process of vegetation. In the case of cer- 

 tain species or families of plants, it would perhaps require many cen- 

 turies to determine the limit of their vegetative powers, yet it is 

 probable that a very few years would suffice to fix the maximum 

 duration of the greater number, and that many interesting results 

 might thus be obtained even by the present generation of botanists. 

 It is proposed then to form a collection of the seeds of a great 

 variety of plants, (including, wherever it is possible, at least one 

 species of every genus,) and to pack them up (carefully labelled) 



