UC-NRLF 
 
 bfil 353 
 
 STUDIES IN WOOD DECAY 1. LABORATORY TESTS ON 
 THE RELATIVE DURABILITY OP SOME WESTERN 
 CONIFEROUS WOODS WITH PARTICULAR RE- 
 FERENCE TO THOSE GROWING IN IDAHO 
 
 University of Idaho, Bulletin No.l. 
 
THE SCHOOL OF FORESTRY 
 
 OF 
 
 THE UNIVERSITY OF IDAHO 
 
 P. G. MILLER, Dean 
 IHLLETIX >0. 1 
 
 STUDIES IN WOOD DECAY I. LABORATORY 
 
 TESTS ON THE RELATIVE DURABILITY 
 
 OF SOME WESTERN CONIFEROUS 
 
 WOODS WITH PARTICULAR 
 
 REFERENCE TO THOSE 
 
 GROWING IN IDAHO 
 
 By 
 HENRY SCHMITZ 
 
 and 
 A. S. DANIELS 
 
 I MVERS1TY OF IDAHO 
 
 Moscow 
 July, 1021 
 
 Entered in the Post Office at Moscow. Idaho, as a University Bulletin; Vol. XVI, No. 16 
 
THE SCHOOL OF FORESTRY 
 
 OF 
 
 THE UNIVERSITY OF IDAHO 
 
 F. G. MILLER, Dean 
 
 BULLETIN NO. 1 
 
 STUDIES IN WOOD DECAY I. LABORATORY 
 
 TESTS ON THE RELATIVE DURABILITY 
 
 OF SOME WESTERN CONIFEROUS 
 
 WOODS WITH PARTICULAR 
 
 REFERENCE TO THOSE 
 
 GROWING IN IDAHO 
 
 By 
 HENRY SCHMITZ 
 
 and 
 A. S. DANIELS 
 
 UNIVERSITY OF IDAHO 
 
 Moscow 
 July, 1921 
 
 Entered in the Post Office at Moscow, Idaho, as a University Bulletin Vol. XVI, No. 16 
 
. 
 
 OFFICERS AND FACULTY OF THE IDAHO SCHOOL 
 OF FORESTRY 
 
 ALFRED H. UPHAM, Pn.D President of the University 
 
 FRANCIS GARNER MILLER, M.F Professor of Forestry 
 
 and Dean of the School 
 
 CHARLES EDWARD BEHRE, M.F Associate Professor 
 
 of Lumbering 
 
 HENRY SCHMITZ, Pn.D Associate Professor 
 
 of Forest Products 
 
 JOHN B. TAYLOR, M.S.F Instructor in Forestry 
 
 INSTRUCTORS IN ASSOCIATED DEPARTMENTS 
 
 MARTIN FULLER ANGELL, Pn.D Professor of Physics 
 
 COL. EDWARD CHRISM AN Professor Military Science 
 
 and Tactics 
 
 HARRISON C. DALE, M.A Professor Economics 
 
 and Political Science 
 
 FLOYD W. GAIL, Pn.D Associate Professor of Botany 
 
 CUTHBERT WRIGHT HICKMAN, B.S.(Ac,R.) . .Professor of Animal 
 
 Husbandry 
 
 CHARLES NEWTON LITTLE, Pn.D Professor of Civil 
 
 Engineering 
 
 FRANCIS BAKER LANEY, PHD., B.S. (M.E.) ..Professor 
 
 of Geology 
 
 GEORGE MOREY MILLER,. Pn.D Professor of English 
 
 EUGENE TAYLOR, M.A Professor of Mathematics 
 
 CARL LEOPOLD VON ENDE, Pn.D Professor of Chemistry 
 
 ALEXANDER R. WEBB, C.E Assistant Professor of Civil 
 
 Engineering 
 
 JERRY EDWARD WODSEDALEK, Pn.D Professor of Zoology 
 
 V. H. YOUNG, Pn.D Professor of Botany 
 
 T. P. JONES Representative for Idaho of Pacific Logging 
 
 Congress 
 
 SPECIAL LECTURERS FROM THE U. S. FOREST SERVICE 
 
 J. A. FITZWATER Lecturer on Forest Management 
 
 C. K. McHARG Lecturer on Forest Administration 
 
 C. C. DELEVAN.. Lecturer on Forest Protection 
 
 Main Library 
 
cs 
 
 STUDIES IN WOOD DECAY II LABORATORY TESTS ON THE 
 
 RELATIVE DURABILITY OF SOME WESTERN CONIFEROUS 
 
 WOODS WITH PARTICULAR REFERENCE TO THOSE 
 
 GROWING IN IDAHO. 
 
 HENRY SCHMITZ and A. S. DANIELS 
 
 Intelligent use is a fundamental concept of conservation. 
 Thus the recent interest in conservation has given an unusual 
 impetus to invesigations making possible a more rational utiliz- 
 ation of the various species of wood. 
 
 Although information concerning the durability of the 
 various American species of wood is rather meagre, Humphrey 2 
 conducted tests on both the heart and sap wood of a representa- 
 tive list of American woods. The results of these experiments 
 were based upon single specimens of each sample of wood and 
 may, therefore, not even be indicative of the relative durability 
 of the various species tested and since many of the specimens 
 became too wet for a fair test, comparisons between his results 
 and those recorded here would be of very little value. 
 
 The painstaking work of Zeller 3 ' 4j 5 marks the beginning 
 of a new era in investigations dealing with the durability of 
 wood. Altho our results are not entirely in accordance with 
 those found by him, it should be remembered that the species of 
 pine investigated in the present study belong to different groups 
 while those studied by Zeller all fall in the hard pine group. 
 
 The work of Schmitz 6 indicates that there may be a great 
 
 1 Several investigations are already in progress in the Forest Products Laboratory, 
 
 University of Idaho, dealing with the decay of wood and it is proposed to give 
 considerable attention to this important line of investigation during the next few 
 years. These investigations will include studies on the durability of the various 
 woods, the value of certain chemicals as preservatives, enzyme action in various 
 wood destroying fungi, and various phases of the general phenomena of wood 
 decav. In order to show the continuity or relationship between these several 
 R'r j em -?' ** is P r P secl to group them under the general title of "Studies in 
 Wood Decay, of which the present article is Number 1. Henry Schmitz. 
 
 2 Humphrey, C. J. Laboratory tests on the durability of American woods I. Flask 
 tests on conifers. Mycoiogia <V: 80-92. pl.l. 1916. 
 
 3 Zeller, S. M. Studies in the physiology of the fungi II. Lenzites saepiaria 
 
 io e n' w ln sP ecial reference to enzyme activity. Ann. Mo. Bot. Card. 3: 439-512. 
 pl.o-y. 1916. 
 
 4 Ibid III. Physical properties of wood in relation to decay induced by Lenzites 
 saepiaria Fries. Ibid. 4: 93-164. pl.9-13.f.l. Charts 1-11. 1917. 
 
 5 Humidity in relation to moisture inbibition by wood and to spore germination on 
 wood. Ibid 7: 51-74. 1920. 
 
 6 Schmitz, H. Studies in the physiology of the fungi VI. The relation of bac- 
 teria to cellulose fermentation induced by fungi with special reference to the decay 
 of wood. Ann. Mo. Bot. Card, 6; 93-136, 1919. 
 
 48290S 
 
4 THE SCHOOL OP FORESTRY, THE UNIVERSITY OP IDAHO 
 
 difference in results obtained under laboratory pure-culture 
 methods and those that would be obtained under natural con- 
 ditions where there is the invariable presence of ordinary types 
 of bacteria. It is therefore hoped that it will be possible to con- 
 tinue this work and extend it to natural conditions. 
 
 PURPOSE 
 
 The purpose of the present study is to test the relative dur- 
 ability under laboratory conditions of the more important coni- 
 ferous woods found in Idaho with the hope of extending the use 
 of the so-called inferior species. 
 
 METHODS AJO) MATEBIALS 
 
 The species of woods used in these fests were selected be- 
 cause of their apparent wide diversity of durability and since 
 they represent the important western commercial woods. They 
 are as follows: western white pine (Pinus montlcola Dougl.), 
 western yellow pine (Pinus ponderosa Lawson), Douglas fir 
 (Pseudotsuga taxifolia (Poir.) Britt), western larch (Larix 
 occidentals Nuttall.), western red cedar (Thuja plicata Don.), 
 white fir (Abies grandis Lindley), and Engelmann spruce 
 (Picea engelmanni Engelmann). The western larch, Engel- 
 mann spruce, western red cedar, western white pine and western 
 yellow pine were obtained from a local lumber yard. The 
 Douglas fir and white fir were donated by the Potlatch Lumber 
 Company, Potlatch, Idaho. 
 
 The fungi used in the present study are : Polyporus lucidus 
 (Lys.) Fries, Lenzites saepiaria Fries, Fomes pinicola Fries, 
 Merulius pinastri (Fries) Burt, Polystictus versicolor (L.) 
 Fries, Pleurotus sapidus Kalchbr, Echinodontium tinctorium 
 Ellis and JLverhart,Trametes fiini Fries, Trametes earned (Nees) 
 Cooke, and Lentinus lepideus Fries. The cultures were obtained 
 either by the tissue method as described by Duggar 7 or the spore 
 method as developed by Zeller 8 . There is no question as to the 
 purity of the cultures. The stock cultures of the fungi are main- 
 tained on both hardwood and pine sawdust and for these experi- 
 ments, transfers were taken from the pine sawdust cultures. 
 
 One inch boards composed entirely of heart wood were 
 obtained and were resawed into blocks measuring 24x1x3 inches. 
 
 7 Duggar, B. M. The principles of mushroom growing and mushroom spawn 
 making. U. S. Dept. Agri., Bur. PI. Ind. Bui. $5. 1-60 pi. 1-7. 1905. 
 
 8 Zeller, S. M. lac. <&. 
 
STUDIES IN WOOD DECAY 5 
 
 The blocks were dried to constant weight in an electric oven at 
 100C. and weighed to the nearest 0.01 gram. Except 
 in the case of Engelmann spruce, ten blocks of each species were 
 placed in each of ten two-quart Mason jars having a layer of 
 absorbent cotton on the bottom. The purpose of the cotton is 
 merely to absorb any excess moisture and thus insure a more 
 even water supply. In the case of Engelmann spruce, eight 
 blocks were placed in each of ten two-quart jars also having the 
 layer of absorbant cotton on the bottom. The blocks were 
 placed on end in every case. 
 
 To each jar 250 cc. of distilled water were added. The 
 amount of water to be added was roughly determined by adding 
 varying amounts of trial flashs so that after sterilization the 
 blocks and cotton were well moistened. In the case of the jars 
 containing larch a small amount of free water remained when 
 sterilization was completed. After a comparatively short time, 
 however, this free water was taken up by the blocks. After the 
 water had been added, the jars were carefully plugged with cotton 
 plugs and sterilized. Sterilization was effected at fifteen pounds 
 pressure for twenty minutes. It may be objected that by this 
 method of sterilization certain volatile components of the resins 
 which might be present in the wood would be driven off. Be 
 that as it may, such very volatile components would soon dis- 
 appear from the wood on exposure to the air and accordingly 
 this would not be a deciding factor in the durability of any par- 
 ticular wood. 
 
 The inoculations were made as follows: transfers from 
 sawdust cultures of the fungi were made to sterile hard agar 
 plates. When practically the entire surface of the plate was 
 grown over with mycelium, it was cut by means of a sterile 
 scalpel into small squares with an area of approximately one 
 square centimeter. With a very few exceptions, a single square 
 was added to each of the culture jars. An effort was made to 
 locate the inoculum in the center of the group of blocks. The 
 fact is of course appreciated that by this method of inoculation 
 the blocks in the center of the group may become infected first 
 and may be well along the road to decay before the mycelium 
 comes in contact with the blocks in the periphery of the group. 
 When wood specimens are subjected to decay under laboratory 
 conditions, there is usually a great diversity in the results for any 
 
6 THE SCHOOL OF FORESTRY, THE UNIVERSITY OF IDAHO 
 
 given wood. This is true whether the individual specimens are 
 in different culture jars or in the .same culture jars. The reasons 
 for this variation are not definitely known and it may merely be 
 the law of "chance" that determines whether or not infection 
 takes place. Whatver it 'be, "chance" or any other factor, that 
 influences the possibility of infection it must, a priori, largely 
 determine the resistance to decay of any specific wood. How- 
 ever, since the cultures were incubated for almost one year and 
 since the average of ten blocks was taken in each case except in 
 that of Engelmann spruce, where an average of eight was taken, 
 it is felt that this fact offers no serious objection. 
 
 After inoculation the culture jars were incubated for a 
 period of 10.5 months at room temperature. It was found neces- 
 sary to water the blocks several times during this period. When- 
 ever this was done, sterile distilled water was added and every 
 effort was made to have the moisture conditions in all of the 
 culture "flasks as nearly the same as possible. 
 
 After the period of incubation, the blocks were again dried 
 to constant weight in an electric oven at 100 C. and weighed. 
 The difference in weight in the two weighings represents the 
 amount of decay. The results for the ten blocks in each jar were 
 averaged and the percent loss in weight calculated on the basis 
 of the dry weight of the wood. 
 
 EESULTS 
 
 In Table I, the average loss in weight percent of ten blocks 
 after ten and one half months' incubation at room temperature is 
 given. 
 
STUDIES IN WOOD DECAY 7 
 
 TABLE I. 
 
 Showing average loss in weight in per cent after ten and a half 
 months' incubation wh^n subjected to the action of the various 
 fungi indicated. 
 
 
 Fungus 
 
 4> 
 
 j* 
 
 <U 
 G 
 
 PH 
 
 
 
 
 
 
 
 | 
 
 
 
 rt 
 
 "Si 
 1 
 
 
 
 ,5 
 
 u 
 
 a 
 
 H-l 
 
 9 
 
 13 
 
 3 
 
 i 
 
 iT 
 
 
 
 o 
 
 o 
 
 3 
 
 a, 
 t/3 
 
 *c3 
 
 !- s ~ 
 
 ~1.1 
 
 zn 
 
 1. 
 
 Polyporus 
 
 14 1 
 
 3 9 
 
 5 5 
 
 5 7 
 
 2 
 
 3 5 
 
 4 1 
 
 5 3 
 
 
 
 
 
 
 
 
 
 
 
 2. 
 
 Lenzites 
 saepiaria 
 
 .50.5 
 
 30.0 
 
 11.8 
 
 5.4 
 
 0.3 
 
 10.6 
 
 9.8 
 
 16.9 
 
 3. 
 
 Fomes 
 pinicola 
 
 28 1 
 
 11 6 
 
 6 7 
 
 7 7 
 
 4 
 
 11 3 
 
 9 3 
 
 10 7 
 
 
 
 
 
 
 
 
 
 
 
 4. 
 
 Merulius 
 pinastri . . . 
 
 3 7 
 
 3 8 
 
 3 1 
 
 * 
 
 3 
 
 2 3 
 
 1 2 
 
 2 4 
 
 
 
 
 
 
 
 
 
 
 
 5, 
 
 Polystictus 
 versicolor 
 
 2 3 
 
 3 1 
 
 1 5 
 
 4 5 
 
 5 
 
 1 3 
 
 2 3 
 
 2 2 
 
 
 
 
 
 
 
 
 
 
 
 6. 
 
 Pleurotus 
 sapidus 
 
 9 4 
 
 3 4 
 
 5 1 
 
 5 1 
 
 3 
 
 2 2 
 
 3 1 
 
 4 
 
 
 
 
 
 
 
 
 
 
 
 7. 
 
 Echinodontium 
 
 5 6 
 
 3 6 
 
 4 6 
 
 6 2 
 
 4 
 
 4 1 
 
 3 8 
 
 4 
 
 
 
 
 
 
 
 
 
 
 
 8. 
 
 Trametes 
 pini 
 
 3 8 
 
 2 2 
 
 3 g 
 
 7 5 
 
 2 
 
 1 4 
 
 2 3 
 
 3 
 
 
 
 
 
 
 
 
 
 
 
 9. 
 
 Trametes 
 carnea 
 
 10 2 
 
 17 4 
 
 12 2 
 
 8 4 
 
 3 
 
 2 
 
 3 9 
 
 7 8 
 
 
 
 
 
 
 
 
 
 
 
 10. 
 
 Lentinus 
 lepideus 
 
 33.0 
 
 39.2 
 
 15.8 
 
 7.3 
 
 0.4 
 
 1.2 
 
 10.6 
 
 15.3 
 
 1 1 
 
 Control 
 
 3 
 
 3 
 
 2 
 
 4 
 
 3 
 
 3 
 
 3 
 
 
 
 
 
 
 
 
 
 
 
 
 i 
 
 \verage loss in weight 
 (all fungi) 
 
 16 1 
 
 '11 8 
 
 7 
 
 6 4 
 
 3 
 
 4 
 
 5 
 
 7 2 
 
 
 
 
 
 
 
 
 
 
 
 * This flask broken by accident. 
 
 A study of the results tabulated in Table I brings out some 
 very interesting points not only relative to the various woods 
 but relative to the action of the various fungi. 
 
 Under the conditions described, the average loss in weight 
 in the woods used due to the action of the fungi is 7.2%. Only 
 white pine and western yellow pine lost more weight than this 
 general average. Douglas rim represented approximately the 
 average loss in weight and western larch, Engelmann spruce, 
 white fir, and western red cedar are below the average, in the 
 order named. 
 
 The maximum amount of decay is caused by the action of 
 
8 THE SCHOOL OF FORESTRY, THE UNIVERSITY OF IDAHO 
 
 Lenzites saepiaria on white pine and the following show less 
 decay in the order named : Lentinus lepideus on western yellow 
 pine, Lentinus lepideus on western white pine, Lenzites saepiaria 
 on western yellow pine and Fomes pinicola on western white 
 pine. It is significant that the five highest rates of decay are 
 found on western white and western yellow pine. The fungi 
 causing these losses in weight are not in any way peculiar to the 
 two species of wood, but are found generally on both coniferous 
 and the hard woods. 
 
 The results in the case of white fir are indeed interesting. 
 Although this wood is usually considered as being very suscepti- 
 ble to decay, under the conditions of these experiments it is only 
 surpassed by western red cedar in its resistance to decay. Even 
 Echinodontium tinctorium, the fungus causing the very prevalent 
 brown heart wood rot of white fir, did not cause even the average 
 amount of decay. This may be explained in part by the fact that 
 the fungus grows rather slowly. The slow rate of growth of 
 Echinolontium tinctorium on hard agar and carrots has been 
 previously reported by Schmitz 9 . 
 
 As anticipated none of the fungi used made any apparent 
 growth on western red cedar. It is evident from the table that 
 the results obtained in the case of each fungus approximate the 
 limit of error as found in the controls for that species. The 
 cause or causes of the durability of this species will be the sub- 
 ject of further investigation in this laboratory. 
 
 The most desructive fungus as shown by the highest average 
 rate of decay is Lenzites saepiaria. The physiology of this 
 fungus has been carefully investigated by Zeller 10 . Lentinus 
 lepidus, Fames pinicola, and Fomes carnea follow in degree of 
 destructiveness in order named. 
 
 Working with various species of pines, Zeller n has shown 
 that "specific gravity or density materially influence resistance 
 to decay of the heartwood, i. e., the more dense the wood, the 
 more durable it is." However, this may be within a genus, it is 
 evident that it does not necessarily hold between different genera 
 since the specific gravity of larch is greater than that of Engel- 
 mann spruce, white fir or cedar. 
 
 9 Schmitz, H. Enzme action in Echinodontium tinetorium. Ellis and Everhart 
 Jour. Gen. Phys. 2: 613-616. 1919. 
 
 10 Zeller, S. M. he. cit. 
 
 11 Zeller, S. M. lac. cit. 
 
STUDIES IN WOOD DECAY 9 
 
 The work of Zeller 13 also indicates that in the case of the 
 various species of pine investigated by him that "the width of the 
 growth rings furnishes a further index of durability, the narrower 
 rings showing more resistance to fungous attack than broad, 
 open rings." The results recorded in the present paper indicate 
 that this relation need not necessarily hold between different 
 genera since the samples of larch used in the present work had 
 an average of 32 rings per inch while white fir had an average 
 of five rings per inch. Even within the genus Pinus, this re- 
 lation did not hold since the western white pine used had an 
 average of 26 rings per inch while the western yellow pine had 
 an average of 12 rings per inch. It is evident that in this case 
 a soft pine is compared with a hard pine while the pines studied 
 by Zeller all belonged to the hard pine group. 
 
 As has been said, the average loss in weight induced by all 
 the fungi on all the woods is 7.2 per cent. A study of Table I 
 indicates that four fungi, namely: Lenzites saepiaria Lentinus 
 lep'idus, Fames pinicola and Fomes earned induced a rate of decay 
 above this average. 
 
 While no direct study was made relative to the rate of 
 growth of the various fungi used, even a cursory observation 
 shows that these four fungi are among the more rapidly growing 
 species. Although Echinodontium tinctorium and Trametes pini 
 are among the more important forms causing heart wood rots in 
 the Northwest the average rate of decay induced by them is low. 
 This, as has been mentioned, may in part be explained by the fact 
 that they are relatively slow growing forms. Even so, the rela- 
 tion between rate of growth and rate of decay need not neces- 
 sarily hold, for example, Polystictus versicolor has a relatively 
 rapid rate of growth but induced a low rate of decay. Detailed 
 information concerning the relative rate of growth of the common 
 and more important wood destroying forms would be of great 
 practical and immediate importance in determining how soon 
 after a fire or other disaster a tree would become badly decayed. 
 
 From a technical and practical point of view, it is evident 
 that under certain conditions, as for example those of these 
 experiments, white fir is not as susceptible to decay as generally 
 thought. When the susceptibility to decay of any wood is con- 
 sidered, the fungus inducing that decay must also be considered. 
 
 13 Zeller, S. M. he. cit. 
 
10 THE SCHOOL OF FORESTRY, THE UNIVERSITY OF IDAHO 
 
 For example, Fomes pinicola induced a higher rate of decay in 
 white fir than in Douglas fir while Fomes earned induced a much 
 higher rate of decay in Douglas fir than in white fir. 
 
 If the average rates of decay are considered, the results indi- 
 cate that with the exception of western red cedar, under the con- 
 ditions of these experiments, white fir is the least susceptible to 
 decay while western white pine is the most susceptible and 
 Douglas fir represents approximately the average degree of 
 durability. 
 
 It is clearly recognized that, however interesting the above 
 results may be, before they can be generally accepted it will be 
 necessary to carry out similar experiments under natural condi- 
 tions. The various species of wood should be used under similar 
 conditions and a careful study of the results made. The School 
 of Forestry is at present carrying on these experiments. 
 
STUDIES IN WOOD DECAY 11 
 
 CONCLUSIONS 
 
 It would seem that, from the results of the preliminary ex- 
 periment above discussed, it would be safe to conclude that : 
 
 1. White fir and Englemann spruce may not be as sus 
 ceptible to decay as generally thought. 
 
 2. When different genera are considered, the specific grav- 
 ity of the wood is not necessarily an indication of its durability. 
 
 3. Within the same genus, the number of annual rings per 
 inch is not necessarily an indication of the durability of the vari- 
 ous species. 
 
 4. Certain fungi causing very prevalent and complete heart 
 rots of standing timber may not induce a high rate of decay due 
 to their slow growth. 
 
 5. The durability of any wood is not only a question of the 
 inherent properties of the wood itself, but also depends upon the 
 species of fungi prevalent in any particular locality in which the 
 wood is used. 
 
 6. Under the conditions of these experiments, western red 
 cedar is the least susceptible to decay, while western white pine 
 is most susceptible and Douglas fir represents approximately the 
 average of durability. 
 
 7. Experiments involving the use of the different species 
 of wood under natural conditions are necessary before final con- 
 clusions can be drawn. 
 
School of Forestry 
 
 University of Idaho 
 
 Four Year Course, with opportunity to sjJtH-ialize in General 
 Forestry, Logging Engineering, and Forest Grazing. 
 
 Forest Ranger Course of high school grade, cpvering two 
 years of five months each. 
 
 Special Short Course covering twelve weeks designed for 
 those who cannot take the time for the fuller courses. 
 
 No tuition is charged for any of the above courses, and 
 otherwise expenses are the lowest. 
 
 Correspondence Course. A course in Lumber and Its Uses 
 is given by correspondence for which a nominal charge 
 is made. 
 
 Advantages. Eighteen National Forests are located in Idaho. 
 The total forested area of the State is 23,000,000 acres and 
 the estimated stand is 130,000,000,000 ft. b.m. This in- 
 sures an abundance of summer work and unusual oppor- 
 tunities for final permanent employment. 
 
 For Further Particulars Address 
 
 Dean, School of Forestry, University of Idaho 
 
 Moscow, Idaho 
 
Gaylord Eros. 
 
 Makers 
 
 Syracuse, N. Y. 
 PAT. JAN, 21, 1908 
 
 YD 02929 
 
 UNIVERSITY QF CAUFORNIA LIBRARY