March a, 1885.] THE TROPICAL AGRICULTURIST. 691 



repose, and growers who have an interest in their plants 

 act accordingly. It must not, however, be supposed that 

 to tap a tree at this time involves any serious peril, for 

 the sap flows very slowly, and in a day or so heals up. 

 When sufficient sap or juice is collected it is poured into 

 a large earthenware pan, and the liquid is dried in suc- 

 cessive layers on a mould formed of clay, until the desired 

 thickness is obtained, or until the juice is all used up. 



The mould is thus made:— A piece of wood of a con- 

 venient length for a handle, about one inch or more in 

 diameter, is coated with a layer of clay about t> or 8 

 inches lung, and from 3 to 5 inches diameter tapering 

 at top and bottom. After drying in the sun it is ready 

 for use. The clay-covered part of the handle is dipped 

 into the juice and moved about so as to facilitate the 

 removal of adherent air-bubbles, and then lifted out, and 

 the handle carefully turned round and round, so as to 

 keep an even thickness or coating all round. Winn this 

 coating is set, another dip is made the additional coat- 

 ing dried, and the operation repeated for as many coat- 

 ings as may be necessary. When finished the whole is 

 held over a fire made by burning the nuts of the I rucari 

 palm fruit until it becomes of a dark rich brown colour. 

 In this state it rapidly darkens. It is becoming more and 

 more rare to find this smoked Para rubber ; this may be 

 due to the scarcity of the palm nuts and the want of a 

 suitable substitute. 



Whatever may be exhalations from the roasting nuts it 

 is evident that the Para rubber so treated may be kept 

 for years without deteriorating. At one time, each coat- 

 ing was dried or coagulated by the heat from these fires. 

 The statements made by some writers on this smoking 

 process are absolutely ludicrous, and suggest the accept- 

 ance second-hand of a description which has been borrowed 

 from a writer who has embellished a description by some 

 one else, and which was probably correct until it received 

 the adornment. The peculiar cooked-like odour of the Para 

 rubber is due to the oil which rises from the burning 

 nuts, and the curious shaped nuts sometimes found in 

 packages of Para or Negrohead rubber are those which 

 are used in this smoking. 



It may be a troublesome thing to prepare Indiarubber 

 in a climate like India, so as to ship it in a condition 

 likely to compete favourably with the rubbers from Brazil 

 and elsewhere, and I would therefore suggest that it may 

 be worth while to try the effect of smoking the prepared 

 masses of Indiarubber directly they are finished. At any 

 rate, the danger from handling might be avoided, as India- 

 rubber in contact with perspiration soon becomes soft and 

 sticky. After the bottle is finished it is cut open by a 

 longitudinal slit, so as to remove the mould; the clay is 

 broken up, and the handle drawn through the neck of the 

 bottle. It is then placed under pressure, when it takes 

 the form of the well-known Para bottle-rubber. It is;a very 

 common thing to find a small hole through the flattened 

 bottles. These holes are made so as to string them to- 

 gether in piles, in which form they are sent by the col- 

 lectors to Para or to the merchants. 



Bates says that the thongs used in threading up the 

 bottle is an air root of an epiphytous plant. On our 

 visits to the forests just outside Para we saw an immense 

 number of these thong-like roots hanging down from the 

 highest branches of the tallest trees, and reaching to the 

 ground. One of our party hung on to one of them with- 

 out its breaking. I do not remember seeing any of these 

 thongs in a package- of Indiarubber. The strength of 

 these thongs must be very great, as one about a quarter 

 of an inch in diameter is quite sufficieut to support about 

 one hundred and fifty pounds of rubber. 



The rubber thus prepared is conveyed by canoes to the 

 ports from which it is exported. The merchants who 

 ship the article obtain it from the natives in exchange or 

 barter for other commodities. The rubber accumulates in 

 the warehouses of these merchants until sufficient is col- 

 lected to make a consignment to a shipper or broker, 

 whence it fin Is its way in this country to the ports of 

 Liverpool and London. This rubber is eagerly sought after 

 by the Am iricans, and there is no doubt that its price is 

 kept up by competition between the English and Amer- 

 ican market-. A great deal of rubber is now shipped direct 

 from Maranham which was formerly sent to Para. The 

 purity of this rubber commands for it a good price. — India- 

 rtfljber and G ■ nal. 



KOOTS.* 



In treating of the roots of plants this evening, I may 

 request you to dismiss from your minds any expectations 

 or apprehensions of marvellous descriptions of tropical or 

 rare roots on the one hand, or of a list of the peculiar- 

 ities of various kinds of roots or so-called roots on the 

 other, though it is not improbable that some of the facts 

 will be, in part at least, new to some of you, as they 

 certainly are to many people. I do not propose even to 

 put any new discoveries before you. It has seemed much 

 more to the purpose to show, as well as time will permit, 

 that a past amount of interesting and important inform- 

 ation can be derived from a proper and systematic study 

 of the roots of a common plant— information, moreover, 

 which is important alike to the scientific botanist and to 

 the practical agriculturist, two people who find they have 

 more and more in common each day they come to know 

 one another better. As the diagrams must in part have 

 told you already, I propose that we meet on ground 

 familiar, to a certain extent, to every one ; and the sequel 

 will show, I hope, that we have in no way acted unwisely 

 in taking each other into confidence on the subject of an 

 ordinary root, such as is well-known to all of us. So 

 much is this the case, that our study may be confined 

 for the most part to the root of the common broad bean 

 and a few other plants of our gard< ns. 



[The lecturer then shortly described the germination of 

 the common bean, maize, and a few other plants, and 

 illustrated by diagrams the mode in which the first or 

 primary root of the bean seedling emerges below, as the 

 young seedling shoot (or " plumule ") prepares to force 

 its way upwards to the light and air. Next followed a 

 short consideration of what this root may be said to be.^ 

 Anticipating matters to a certain extent, it may be shortly 

 described as an organ for fixing the rest of the plant to 

 the substratum or soil from which it absorbs certain food 

 materials. By confining our attention to this typical and 

 well-known form of root, we may avoid any complexities 

 resulting from the consideration of the more extraordinary 

 cases occurring among the lower plants, or among curious 

 aerial epiphytes, parasitic or otherwise, and other abnormal 

 forms — forms which would demand several lectures by 

 themselves, 



The roots we have to consider, then, are organs for an- 

 choring the rest of the plant firmly into the soil, and for 

 absorbing certain matter dissolved in water from that soil. 

 Obviously, we may do well to see, first, how the root gets 

 into the soil ; and secondly, how it accomplishes its objects 

 when there. 



When the young root first peeps forth from between 

 the coats of the seed, it is seen to have its tip directed 

 downwards towards the centre of the earth. Now this is 

 not an accident; for .if the seed be turned over, so that 

 the apex of the root is made to turn upwards, its tip 

 soon In tt'ls over, and again becomes directed dowuwards. 

 [Mr. Ward then proceeded to explain, as shortly as could 

 be done without detailed experimental evidence, that this 

 persistent turning earthwards of the young root is due 

 to a peculiar property, almost of the nature of a sensitive - 

 ness or perception to the influence of gravitation, and is 

 not due merely to the weight of the organ.] 



Next, evidence has been obtained to show that the 

 tip of the root has a slightly rocking or swinging move- 

 ment, which is more or less of the nature of the movements 

 so well-known in the case of the stems of twining 

 plants; the tip of the root, in fact, not only move6 

 earthwards, but tends to' describe a very steep spiral as 

 it does so. These successive very slight noddiugs to all 

 sides of the tip as it proceeds in a line directed towards 

 the centre of the earth are extremely slight, it must be 

 borne in mind, but they may aid the point of the root 

 to wriggle its way between the particles of earth in a 

 loose soil, or to rim down any crevice or bole it meets 

 with. 



Thirdly, in addition to its determined tendency to de- 

 scend, though in a very slightly spiral course, the tip of 

 such a root as we are describing has been found to be 



* Abstractof a lecture delivered before the Manchester 

 Horticultural Society, in the old Town Hall, Manchester. 

 on November G, by H. Marshall Ward, M. A. Fellow of 

 Christ's College, Cambridge, and Assistant Lecturer in 



Botany at the Owens College. 



