9

H.—34,

Percentages of Description of Fibre. Moisture. Ash. Volatile Oil. Fixed Oil. Total Oil. A. Native—good ... ... 1374 -74 29 -20 -49 B. Machine dressed—good ... 1332 -63 -14 -29 -43 C. Machine dressed—ordinary 12 79 . -51 -38 -26 -64 D. Nichol's process ... 1417 -70 '56 -3G '92 In the following series of experiments, the samples called A, B, and C in the above table were employed.

Oiling Experiments, Series I. Oil used, paraffine lubricating or machinery oil, having the specific gravity *9243. The fibres used were in their ordinary condition as to hygroscopic moisture. They were thoroughly saturated with the oil, and then submitted to pressure and hammering to remove all excess of oil. The following numbers represent the final percentages of oil absorbed and retained by the several samples of Phormium fibre, two experiments being made in each case, and numerous weighings : — Absorption of Mineral Oil {Paraffine Oil) by Fibres. A. Native —good. B. Machine—good. C. Machine—ordinary. -o c ~ , . , ( 1211 19*41 2225 Percentage ot oil retained j 18*80 2066 ''4*97 Mean ... 1270 2003 2361 Tn order to see how far these numbers really represented the percentages of oil retained by the several samples, it was necessary to ascertain whether the absorption of oil had been accompanied by any loss of hygroscopic moisture. The samples used in this series were therefore reweighed and dried till constant in weight in vacuo over oil of vitriol. The loss of water they then suffered sufficiently proved that the absorption of the oil had driven out but little if any of the natural moisture of the fibres. A. Native —good. B. Machine—good. C. Machine —ordinary. Percentage of water lost by f 1079 952 891 oiled fibres in vacuo. I 11*63 1034 964 Mean ... 1121 993 93 It thus appears that the fine Native-dressed fibre absorbs least oil and retains during such absorption the highest percentage of hygroscopic moisture. In order further to test the accuracy of the determinations of oil retained by the fibres, direct determinations by means of the " ether process " were made. The prepared and oiled samples which had been dried in vacuo contained the following amounts of oil in 100 parts : — A. Native—good. B. Machine—good. C. Machine—ordinary. Percentage of oil retained | v 17 _ 14 20 . g8 by the fibre, but removed V -^ 1g . 91 2 g by ether ... ... ■■■ ) Mean 11*27 18*03 2057 These numbers accord as closely as could be expected with those given in the first table, and show that the fine Native-dressed fibre retains the least oil amongst the samples tried. Oiling Experiments, Series 11. The oil used was the same as that of Series 1., but the fibres were dried at 100° centigrade (212° Fahrenheit) previous to their being soaked in the oil. It was thought that the removal of the hygroscopic moisture from the fibres would increase the quantity of oil absorbed, and render its penetration into the fibres more thorough. This anticipation was not realized, for less oil was absorbed under the single altered condition (of previous drying) of these experiments. The percentages of oil retained by dry fibre, after pressing and hammering, as in Series 1., were as follows : — A. Native —good. B. Machine —good. C. Machine—ordinary. Per centage of oil retained "} „,„, 19-34 1"*67 by fibres which had been , 819 15 . 3( . previously dried ... ... ) Mean 825 1350 1552 Thus we learn that dry fibres absorb less oil than those which are naturally moist; and that the fine Native fibre retains the same position as to the percentage of oil which it held in the first series of experiments. From other trials I conclude that drying the fibres previous to oiling or tarring them will prevent the sufficient absorption of the liquid used, while submitting the fibres to a moisture-laden atmosphere may prove beneficial, especially if they be subsequently dried, —that is, after the treatment with oil, &c. Oiling Experiments, Series 111. The oil now used was a colza oil, of sp. gr. *910. The fibres used were from the same samples as before : the operations of pressing and hammering were conducted in the same manner. The experiments, however, were not very successful or uniform in their results ; and the inferiority of a vegetable oil for such purposes was shown by the appearance of the samples after treatment. The following 2—H. 34.