252 
10. Rub together, on a plate or stone, a little fresh-slacked 
lime, with four times the same quantity of Guano; put it into a 
wide-mouthed bottle; you will then have evidence, from the 
smell, not only of the abundant quantity of Ammonia which it 
possesses, but also of the impropriety of mixing lime with 
it, for use; seeing that the ammonia is liberated, and would be 
lost in the atmosphere. 
Lastly. It is better to use too little than too much. 
214. Alkalies; their effects. Since the alkali, called Am- 
monia, is found so abundantly in Guano, the following article, 
which we copy from the Records of Science, may not inappro- 
priately follow the preceding subject. A correspondent of that 
work says, “ During last summer I performed a series of expe- 
riments, with a view to ascertain what effect various substances 
had in supporting vegetable growth. For this purpose I pro- 
cured several plants, and placed them in vessels of water, adding 
to each, various proportions of alkaline salts, and other matters. 
Now, I found that more than one-thousandth part of potassa, 
soda, or their salts, would prove injurious, rendering the plant 
sickly or destroying it, according to the strength of the solution. 
By adding a thousandth part only, I found the plant invigorated 
and decidedly more healthy than those plants which were in 
water alone. Some of these plants existed in these vehicles for 
six or eight weeks, and to all appearance would have lived 
longer had I prolonged the experiment, but they required 
renewing with the stimulants after the space of twelve, twenty- 
four, or thirty -six hours, according to the size of the plant; 
for water rendered alkaline by carbonate of soda, for instance, 
to the strength above mentioned, although it would at the time 
turn reddened litmus paper blue, and display its presence on 
turmeric paper, yet, after a lapse of some hours, the water ceased 
to possess these properties, and even the plants, if cut trans- 
versely near the lower part, although the alkali had been absorbed, 
would denote the presence of a free acid. Beneficial as were the 
alkalies, still more visible developement ensued from those 
vessels wherein I had placed the oxide of iron and of zinc, these 
would bear a larger quantity than the former, as they are less 
soluble in water, and not so abundantly absorbed — still, after 
some time standing, it seemed their solubility was increased, 
probably from the secretion of some acid from the plant 
