62 
ANNALS OF THB 
our views on the subject of the Chemistry of Plants, more especially with regard to 
the sources of plant food.. The above researches have also an important bearing in 
this respect, and if borne out by further investigation will lead us to attach still 
more importance to the atmosphere as a source of plant food. 
In connection with this subject it may be mentioned that there is a singular 
want of direct and satisfactory experiments as to the real value, as a manurial ap- 
plication to the soil, of the mineral phosphate of lime, Apatite. Judging from the 
number of Canadian specimens that have been lately brought to the Laboratory of 
Queen's College for examination and analysis, an abundant supply of this material 
might be exported from Canada for agricultural purposes. The attention of English 
agriculturists is therefore invited to the subject. 
Sea-Weed as a Manure. — The attention of the English farmer has been re- 
cently called to the use of sea-weed as a manure. This material is thrown up in 
enormous quantities on the shores of Britain, and on the east coast of Scotland it is 
extensively employed to fertilize sand dunes that would otherwise be worthless. In 
dry sandy soils it acts in two ways ; first, by directly contributing food materials to 
the crop, and, secondly, by the hygroscopic action of the mucilaginous tissues in 
maintaining a certain degree of humidity in the arid soil, a result that is no doubt 
aided by the presence of the sea-salt accompanying the weed. The richness of the 
ash of the common sea-weed in potash^ soda, phosphates, and other materials of 
plant growth, shows that it has a high manurial value. In Greenland specimens, 
the ash has been found to contain ten per cent of phosphates. The proportion of 
water in the recent weed is so large, however, that sea-weed cannot be profitably 
carried to great distances, but along the shores of the lower St. Lawrence and in 
the other maritime provinces, where it can be readily obtained at certain seasons, 
its value can scarcely be over-rated. The processes that have been suggested for 
converting the sea-weed into a paste for transport, mixing with peat ashes, &c., do 
not seem likely to lead to any useful result, so far as the British American provinces 
are concerned. 
Steeps for Seeds. — Of the many "steeps" that have been recommended 
to facilitate the germination of seeds, the most intelligible is that of caustic potash, 
or carbonate of potash, applied by M. Andre Seroy to seeds naturally protected by 
fatty or oily pulp. He reports that the seeds of Hollies, Magnolias, Yews, and the 
like, which often lie dormant in the ground for a couple of years, come up readily 
after treatment with potash and subsequent rubbing with sand. 
Blanching of Flowers. — It is well known that light is as necessary to plants 
as a due supply of heat and moisture. The effects of its absence are often singular. 
"We know that plants grown in darkness do not exhibit their usual healthy green 
color, light being required for the development of chlorophyll. Advantage is 
i^keu of this circumstance in the blanching of salads and vegetables, and the same 
