October i, 1891.] THP TROPICAL AGRICULTURIST. 
The pracfcioa of p'acins; green boughs of the eucalyptus 
or blue gam tree iu sick-rooms as a disinfectant is grow- 
ing in Ausrralia. Dr. Ourgenveu states that if placed 
under tho bed in cases of scarlet fever they will i horougli- 
ly disinfect the couch and every article in the room. The 
volatile scent has aho a favourable influence on con- 
sumptive patients, as an antiseptic and eedativi'j 
tending to promote sleep.— G'Zoi?. 
• 
ARTIFICIAL RAIN. 
The manufacture of rain has, for longer than 
it is easy or pleasant to remember, ceased to be 
of the slightest practical interest in this country. 
If anybody would patent an invention for the 
manufacture of sunshine and dry weather, even 
if it were no more than the Laputans got from 
cucumbers, he would des'^rve a statue. But we 
must not be so selfish as to close our sympathies 
to districts which actually envy the state of 
Cornwall, where, according to the proverb (now 
apparently requiring extension beyond the borders 
of the Duchy) it rains once every day except 
on Sundays — when it rains twice. In Texas, it 
Seems, they have been cloud compelling with 
startling success. In a district where for more 
than three years no rain has fallen save in very 
occasional small showers, and under atmoepherio 
conditions considered incompatible with rain 
enough to melt a pinch of salt, an explosion of 
oxygen and hydrogen from five balloons at various 
heights brought a sharp clup of thunder, followed 
by heavy rain within about five hours. For five 
hours the rain went on, displaying a beautiful 
rainbow at sunrise ; the first recorded instance, so 
far as we are aware, of the manufacture of a 
real rainbow. The details of the whole process 
are minute; they are based, it need not be said, 
on the constant experience of rain after big battles, 
and the continual aerial explosions in Texas 
no doubt cheated the spirits of the storm into 
thinking that they were called in to assist at 
a favourite and familiar human pastime. The 
question of course remains whether they will 
always consent to be tricked into thinking that 
there is a big fight when there is nothing of the 
kind. Meanwhile it is gratifying not to live in 
Texas, if nightly bombardments of dynamite and 
explosive gas are to be among the phenomena 
of practical farming, We have noise enough of 
our own, as things are ; and happy therefore is 
the land whose rain, like the poet, is born, and 
not m&ie.—Olobe. 
PAPAIN: THE VEGETABLE PEPSIN. 
It is one of the concomitants of the advance of 
human civilization, and perhaps a form of the Nemesis 
that follows man's neglect of nature's dictates, that 
as his power over the material increases and as he 
accumulates wealth and knowledge his physical being 
tends to imdergo a kind of retrogression, and becomes 
less able to bear the strain imposed upon it by an 
active and almost unwearying intellect. 
Thus it is that one of the characteristc features of 
the age is the number and variety of the devices 
for remedying the defect alluded to, sought after and 
introduced, prominent among which must be classed 
the ever increasing array of preparations for facilitat- 
ing digestion, and remedj'ing the evils resulting from 
confused and sedentary habits of life, combined with 
hurried and unnatural systems of supplying the 
severely taxed frame with nutriment. 
Of artificial digestive agents few have been more 
conspicuous than the pepsins, which being natural 
peptonizing substances, are apparently most suited to 
euhanco the functional activity of an infeebled 
stomach. It is, however, well recognized that pepsin 
is not a definite body and that, as a matter of tact, 
its BftUue will Yftvy accgirtliug t9 the metiigtls 9i pi'e- 
paration ; it seems to be further inevitable that, by 
whatever process it is isolated, a considerable pro- 
portion of mucus and similar substances will be present. 
The fact that pepsins are of animal origin, has 
been the source of some amount of repugnance lo 
their use, both on the part of patients and of phy- 
sicians ; the tendency of modern medicine has been 
to abandon the internal employment of members of 
the animal materia medica, and against this tendency 
the introduction evidently militates. Again, it has been 
pointed out, that the excretion of ptomaines or cada- 
vric alkaloids ceases in the animal body simulta- 
laeously with the arrest of the vital functions, so that 
it is not at all impossible that carelessly made 
specimens of pepsin might be contaminated with 
animal ferments or the products of their action upon 
the devitalized tissues. This danger is the more prob- 
able as consistently with the preparation of an active 
substance, sufficiently high temperatures caimot be 
employed iu the isolation of the digestive agent to 
destroy the ptomaines possibly present. 
In view of these objections to pepsin and the 
allied agent pancreatiu, a good deal of interest was 
excited by the earlier accounts of the wonderful 
properities of the fruits of the papaw tree, a native 
of tropical America, which was credited with the 
power of disintegrating and more or less completely 
digesting flesh simply hung beneath its branches. 
Carica papaya, belonging to the natural order 
papayacese, is a tree which grows to about 20 feet 
in height and 2 feet in diameter. It is easily and 
quickly raised from seed, attaining a thickness of 
1 foot by the third year and commencing to decay 
during the fourth or fifth year. The siraight and 
undivided stem is herbaceous and soft, though it de- 
velops an external layer of fibrous tissue ; as might 
be expected from the rapidity with which it grows, 
the trunk is hollow, though at irregular intervals 
it has more or less dense, imperfect septa. The 
newer parts of the stem are green, but as they age 
become greyish; towards the top it also bears the 
scars formed by the falling ofi' of leaves., which are 
arranged in a kind of umbellate canopy. 
The large palmately cleft leaves are borne upon 
long petioles, from the bases of which the pale 
yellow flowers originate. Like other species of the 
same order the flowers of the papaw are unisexual. 
The staminate flowers are borne upon a long ped. 
uncle in a racemose form, while the pistilate flowers 
are sessile. 
The tree continually flowers and simultaneously 
bears fruit, the latter ripening at the lower part of 
the crown of foliage while the flowers are just 
opening at the apex. The flowers, as also some other 
parts of the plant, resemble Indian cress — the 
nasturtium of the garden — in order and taste. 
The fruits are somewhat melon-like in form, or 
they may be more ovoid and pointed at the apex. 
When first formed they are green, but as they mature 
they become yellow or dull orange colored. A large 
fruit is said to sometimes attain a weight of 10 
poimds. The rind is thin, and within it is the 
yellowish flesh, with a pleasant sweet taste, enclosing 
a cavity containing the dark brown or black seeds. 
By the natives of the districts where it grows the 
fruit of Carica is largely consumed and regarded as 
highly nutritious. The milky juice of the unripe 
fruit omd the powdered seeds have the reputation of 
being powerful anthelmintics, and it was further 
reported, that the former had the property 
of softening the toughest meat when boiled with it 
for a short time. Some parts of the plant were 
esteemed as vulnearies, and the juice of the ripened 
fruit was said to be useful in removing freckles and 
spots from the complexion. 
These reports naturally attracted considerable 
attention, and the juice was subjected to analysis by a 
number of chemists. Vauqueliu found that the juice 
resembles animal albumen in its characters, and 
Wittstein stated that it contained a ferment which 
had a most energetic action on nitrogenous substances. 
The leaves, like most other parts of the plant, yield 
a neutral, yellow, milky juice, with a sharp bitter 
taate, which by tbe addition of eugtr, glycerine, e(b9 
