1070 G. ROSSI 



pliance for mechanical washing of the retted hemp. Drying is carried out 

 in the open air as in ordinary retting. 



On the other hand the matter becomes more comphcated where the 



retting is preceded by green scutching. Nevertheless the latter is alwaj's 



preferable, because this system carries with it the following advantf^.ges : 



(i) If the scutching is done in the field, only about half the weight 



of raw material will have to be carried to the retting appliance. 



(2) During retting, the macerating capacity will be a little more than 

 1/3 superior to that of retting as practised in the coimtry district s, hence : 



(3) The reduction of the bulk to be treated means a reduction of 

 vat area in the proportion of 2/3. 



(4) A reduction of '^/g in water consumption. 



(5) A reduction of ^/g in consumption of heat and air. 



Moreover, it is only by scutching first of all that one of the advantages 

 of industrial methods generally, and the one we advocate in particular, 

 can be really turned to account. The methods consists in the following : 



(6) The work can be carried out throughout the year. Artificial 

 drying of the stalk would entail enormous expense. Industrial stalk ret- 

 ting is only conceivable during the good season. Precisely the contrary 

 is the case in the retting of the alread}^ scutched material, and drying i^; 

 then one of the easiest operations. 



It should also be remarked that these observations on the advantages 

 of scutching before retting presuppose of course that scutching is possible 

 per se in the first place, and then in relation to the subsequent retting of 

 the fibres. 



It can be proved that scutching is possible, though there are prejudices 

 against it which are chiefl}^ based on the fact that up till now mecha- 

 nical white scutching or breaking of the retted stalk hemp en the country 

 method is a problem for which no satisfactory solution has been found. 

 There is no mechanical scutcher obviating the necessity of afterwards 

 breaking the hemp by machine, or, better still, hand crushing it, or both 

 together. There is also no method w^hich does not leave a considerable 

 quantity of tow and leave the harl very tangled. 



On the other hand, there are scutchers capable of reducing from 38 

 to 61 % of the weight of the stalk, according to the quantity of the hemp, 

 and which turn out inconsiderable quantities of tow. 



These figures prove, it is true, that when scutching is finished, the resul- 

 ting harl is still made up, to the extent of 50.2 to 46.7 %, and at very least 

 28.3 %, of stalk, but this is not a drawback, because retting by its very 

 properties as easily effects detachment of the harl from the woody parts 

 as do the operations of beating and, above all, washing; finally, however, the 

 drying and softening of the harl, cause the disappearance of all the remain- 

 ing stalk. 



It is true, however, that scutching remains a fairly delicate operation, 

 because a given machine is not always adapted for handling all kinds of 

 hemp. It has moreover been found that green scutching is more dis- 



