704 
THE TROPICAL 
AGRICULTURIST. [February i, 1882. 
ported. Two-thirds of the peppermint oil of this country 
is produced in New York State, and about one-third in 
Michigan. The best oil comes from Wayne County, New 
York. The plant is a perennial one, and is planted in 
the spring. The next year it is ready for cutting, and 
generally may be cut for three years. 
The best yield is given in the first and second year 
of cutting ; in the third year the plant becomes bitter. 
After the plant becomes four years old it is not cut, and 
the field is ploughed over and a new crop planted. The 
usual method of planting is in rows, and in August the 
plant is ready for cutting, which is done by mowing 
down with a scythe. The leaves are then placed in a 
still and the oil extracted. There was a report that a 
considerable number of the roots were damaged by the 
cold weather of last winter, but it is claimed that this 
will not affect the price, as there is an increased acreage, 
and the damage is not as great as has been claimed. The 
plant is a very hardy one, and will yield from ten to thirty 
pounds to the acre. The cultivation of the peppermint is 
now being introduced into the Southern States, where it 
will furnish a profitable crop in the middle of the year, 
but as yet none of the Southern oil has reached this market. 
INFLUENCE OF RAINFALl7~0N WELLS 
AND RIVERS. 
(Field, 12th November 1881) 
Some new sources of occupation and interest for 
those with time to dispose of are suggested by Mr. 
Joseph Lucas, F.G.S., in a pamphlet which appears 
monthly on the "Wells, Springs, and Rivers of Great 
Britain," published by Vacherand Sons, 29, Parliament- 
street. "There are thousands of persons in this country," 
says Mr. Lucas, " who have the opportunity of adding 
to our stock of knowledge valuable contributions by 
simply meisuring the depth of water in their wells 
each day. Th re aie thousands of others, residents 
near streams, who might perform an equal service 
to themselves and their fellow-men by measuring the 
distance of the river below a fixed mark every day." 
The depth of the water in a well, as everyone knows, 
is not a constant quantity. It varies wiih the season 
of the year — that is to say, wiih ihe rainfall, and 
also with the demands made upon it. There is utility 
in ascertaining how the level of water changes by 
drought or by the heavy pumping of wells in the 
same basia. It furnishes data from which the quantity 
of available water can be calculated. Again, it is 
interesting to note how some wells rush up rapidly 
aftei a rainfall, and how they subside during dry 
weather. Such are usually very shallow wells. The 
deeper wells lake a sensibly longer time to feel the 
effect of rainfalls, so the rapid fluctuations in the 
readings of the water level in a deep well may 
lead to the discovery, otherwise ditiicult to ascertain, 
of faults or subterranean cracks, permitting surface 
water to descend with rapidity into deeply-buried 
strata. As the editor of the pamphlet remark?, "It 
may be safely averred that, if anyone who is not 
already in the habit of doiDg so should begin to 
observe the daily variations of the water in his well, 
he will not readily give up the hah t. By the constant 
change of level of the water in his well, a curiosity 
as to the state of the water-line is excited, which 
is not sa'isfied until the position of the water is 
determined by a new measurement." Such investig- 
at OHS will be of interest, even from isolated observers, 
butthe maximum inf ormation would only he derived 
when several pe so is experiment and compare observ- 
ations in the same locality. 
Persons of a high degree of enthusiasm may proc eed 
still further, a id endeavour to ascertain what pro 
portion of the rainfall sink* into the earth to replenish 
thi a 'terranoan water sy-tem. This> may be asc-rtoined 
by compari g the rain-gauge result? with t' e amount 
of water which percolates through a cylinder of a 
depth of some few feet, containing soil in its natural 
condition. Besides that which sinks into the earth, 
the quantity which flows off it is worth ascertaining, 
and the informa'ion is not difficult to get. "Few 
bridges are without a 'broad arrow,' or ' bench, mark ' 
"as it is call d, cut by the Ordnance surveyors in 
so ne cqiispicious place, and of w hich the h ight above 
mean sea level (Ordnance datum) is known and recorded 
on the Ordnance maps; and from these marks it is 
ea<y to measure to the surface i f the stream. Even 
when there is no such mark, it is easy to make a 
mark on the parapet, and to determine its level in 
the ordinary manner from the nearest Ordnance bench 
mark. Now, what is the service the observer thus 
performs? Simply this. The section of the river at 
that po nt and its velocities being determined, he 
gives us 1 he gauging of the water at each height. By 
the labour of one minute daily, he gathers inform- 
ation i f potential value to himself and his fellow-men. 
Then, again, there are in this island thousands of 
other persons iu a position to make daily observations 
on the volumes of springs as they issue from the earth. 
In many case , by erecting a small gau-ing board, 
this observation may be made even easier than any 
of the foregoing. Moreover, in certain positions, when 
neither wells, rivers, or springs are accessible to 
observation, information of a most interesting kind 
may be gained by simil ir observations on the height 
of the water in punds. And what is wanted to do 
all this ? Nothing but a foot rule, with which the 
village carpenter is already provided — not a real foot 
rule, forsooth in most cases but a measure graduated 
in feet and inches, of sufficient length fo • the particular 
purpose for which it may be required." 
Mr. Lucas, in addition to experiments as to quantity, 
suggests that the quality of the water may be judged 
by such observations ; but he does no', we think, 
develope the subject as he miyht have done. It is 
well known that the chief objection to shallow wells 
is the facility with which the drainage of cesspools 
and noxious surface water gain access to them Care- 
ful measurements might frequently reveal such clangers 
when they would otherwise remain concealed. A 
shallow w : ell, for example, which contains » ater when 
its neighbours of equal depth are dry, might, on 
inquiry, prove to be deriving its surplus from un- 
pleasant sources; whilst, as we have suggested above, 
if. a deep well, instead of acknowledging a rainfall 
by a gently rising curve, give an almost instantaneous 
bound, it would indicate subterranean channels more 
easy to traverse than proper soil percolation 
Mr. Lucas says: "A water which dribbles in ex- 
ceedingly small quantities through the interstices of 
a rock w ill gen rally, if not always, be found to be 
supercharge d with mineral ingredients or salts — in 
other words, an excessively hard water. It Would, 
therefoie, be desirable, wherever possible, to ascert- 
ain the hardness of water under observation." There 
is a good deal of truth in the above observations, 
but the author has apparently forgotten one thing — 
that is, that the water of surface wells are frequently 
as hard, and oftentimes much harder than that of i 
deep wells, due, not, of course, to percolation, but 
to sewage, which, in addition to its own mineral 
ingredients, obtains more by its energetic chemical 
cation on the Foil. Hence the estimation of hardness 
i j useful, but it would not necessarily give the data 
Mr. Lucas wants. Of course, another characteristic of 
deep w, lis would be its uniform temperature as com.3 
pared with those near the surface. 
A 1 the end of Mr. Lucas's pamphlet are de ails 
of the observations of such gentlemen as h ive alieady 
joind the movement, and we feel convinced that in- 
formation of this character, if properly car. ied out 
and compiled, will be of the highest value, b, th to the 
individual observer and fo the nation at large. We 
trust, therefore, that the matter will be warmly taken up, 
