The Carbon-14 Dating of an Iron Bloom Associated with the Voyages

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The Carbon-14 Dating of an Iron Bloom Associated with the Voyages of Sir Martin Frobisher EDWARD V. SAYRE, G A R M A N HARBOTTLE, and R A Y M O N D W. STOENNER— Brookhaven National Laboratory, Department of Chemistry, Upton, N Y 11973 WILCOMB WASHBURN—Smithsonian Institution, Office of American Studies, Washington, D.C. 20560 JACQUELINE S. OLIN—Smithsonian Institution, Conservation-Analytical Laboratory, Washington, D.C. 20560 WILLIAM FITZHUGH—Smithsonian Institution, Department of Anthropology, Washington, D.C. 20560

There have recently been significant advances in the technique of carbon 14 measurements, which have permitted the determination of the concentration ratio C14/C12 in samples of small size. Two developments have occurred: the first is an entirely new mass-spectrometric separation of C14 and C12 ions and their subsequent estimation by counting [1-8] , while the second is simply the extension of conventional proportional counter operation to very small size carbon samples [9]. The first method is very fast, precise, and capable of treating samples of even sub-milligram size, but requires an expensive installation. The second method is slow (counting times of two months or more are necessary), can probably be made sufficiently precise to handle most problems, works down to sample sizes of 10 mg carbon, and is relatively inexpensive, especially to install in already-existing radiocarbon laboratories. Development of proportional counters to measure C14/C12 ratios in 10 mg carbon samples was undertaken in the Chemistry Department of Brookhaven National Laboratory in 1975 [10] for two 1

reasons: (1) a t the time, there was no other p o s s i b i l i t y i n s i g h t to accomplish t h e g e n e r a l l y much-needed o b j e c t i v e o f small-sample CI4 measurement, and ( 2 ) there was a p a r t i c u l a r carbon 14 d a t i n g problem a t the Smithsonian I n s t i t u t i o n , which would only be solved i f very small carbon samples could be handled. The development and t e s t i n g o f t h e counters has a l r e a d y been reported [ 9 ] ; i n t h e present paper we d i s c u s s t h e a p p l i c a t i o n o f those counters t o t h e a c t u a l d a t i n g problem which concerned the Smithsonian I n s t i t u t i o n , the d a t i n g o f the " F r o b i s h e r i r o n bloom". The " F r o b i s h e r bloom" has a c u r i o u s h i s t o r y , which has been t o l d i n d e t a i l by Stefansson [11] but which bears recounting i n b r i e f here. The noted E n g l i s h E l i z a b e t h a n e x p l o r e r F r o b i s h e r made f i g u r e s i n brackets i n d i c a t e the l i t e r a t u r e references end o f t h i s paper. 0097-6156/82/0176-0441$05.00/0 © 1982 American Chemical Society Currie; Nuclear and Chemical Dating Techniques ACS Symposium Series; American Chemical Society: Washington, DC, 1982.

a t the


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three voyages, i n 1576, 1577 and 1578, t o the North American mainland i n the v i c i n i t y o f B a f f i n I s l a n d , Canada. The f i r s t voyage was intended t o d i s c o v e r a s h o r t - c u t t o China, but the second and t h i r d voyages were a f t e r g o l d , based on a mistaken ( p o s i t i v e ) g o l d assay c a r r i e d out on rock brought back from the f i r s t voyage [12]. The rocks found by F r o b i s h e r have been iden t i f i e d by Roy [13] as amphibolite and pyroxenite. Roy d i d not f i n d " f o o l ' s g o l d " ( p y r i t e ) and surmises t h a t the b r o n z e - l u s t e r e d mica might have been the b a s i s f o r t r i g g e r i n g t h e "gold rush" o f 1577-1578. The i s l a n d s t h a t dot F r o b i s h e r Bay, where the "gold ore" was mined on the second and t h i r d voyages, are i n an out-of-the-way corner o f an i n h o s p i t a b l e land. I t was only i n 1861-1862 t h a t the American e x p l o r e r , Capt. C. F. H a l l , heard from l o c a l I n n u i t (Eskimos) o f e a r l i e r European s i t e s and a r t i f a c t s from t h i s area. F o l l o w i n g these leads H a l l v i s i t e d Kodlunarn I s l a n d and the surrounding area and discovered many t r a c e s and r e l i c s o f F r o b i s h e r s i l l - f a t e d venture [11,13,14], i n c l u d i n g the deep mining trenches, b i t s o f coal and f l i n t , fragments o f t i l e , g l a s s , wood and p o t t e r y and r u i n s o f three stone houses. On Countess o f Warwick I s l a n d (Eskimo name "Kodlunarn" o r "White men's i s l a n d " ) H a l l discovered " i r o n time-eaten, w i t h ragged t e e t h , weighing from f i f t e e n t o twenty pounds, on the top o f a g r a n i t e rock, j u s t w i t h i n reach o f high t i d e a t f u l l change o f moon". Here he a l s o discovered another o b j e c t : "a p i e c e o f i r o n , s e m i - s p h e r i c a l i n shape, weighing twenty pounds ... under the stone t h a t had been excavated f o r the 'ship's way"'. The "ship's way" was a long narrow excavation t h a t had the appearance o f a dry dock. This p i e c e o f i r o n H a l l d e s c r i b e d as being o f the same c h a r a c t e r as t h a t found a t Tikkoon, l e s s than one m i l e from Kodlunarn i n Countess o f Warwick Sound and a l s o as t h a t obtained on "Look-out" I s l a n d , F i e l d Bay. H a l l sent the p i e c e o f i r o n found i n the s h i p ' s trench t o "the B r i t i s h government e a r l y i n the year 1863, through the Royal Geographical S o c i e t y o f London" [15]. In 1927 Kodlunarn I s l a n d was again v i s i t e d , i n the course o f the Rawson-MacMillan e x p e d i t i o n sponsored by t h e F i e l d Museum o f Chicago [11,13,16]. Dr. Duncan Strong, a r c h a e o l o g i s t on the e x p e d i t i o n , looked f o r V i k i n g graves o r other t r a c e s , but found none. Very e v i d e n t , however, were the already-observed remains of the F r o b i s h e r voyages. I n t e r e s t i n g l y , the 1927 e x p e d i t i o n d i d f i n d "a fragment o f p o r c e l a i n ... w i t h m e t a l l i c s l a g adhering o u t s i d e the r i m as though the v e s s e l had served as a c r u c i b l e . " [11]. This i s o f i n t e r e s t w i t h regard t o the record t h a t F r o b i s h e r ' s team i n c l u d e d miners and g o l d - r e f i n e r s . H a l l was convinced t h a t the o r i g i n s o f a l l o f the a r t i f a c t s he had found were the voyages made by M a r t i n Frobisher. To safeguard them f o r p o s t e r i t y , and because he was an American and F r o b i s h e r an Englishman, he d i v i d e d them between the Smithsonian I n s t i t u t i o n i n Washington and the Royal Geographical S o c i e t y i n London. But by the time Stefansson was w r i t i n g , i n the mid 1930's, both o r g a n i z a t i o n s had t o t a l l y l o s t o r m i s l a i d t h e i r 1

Currie; Nuclear and Chemical Dating Techniques ACS Symposium Series; American Chemical Society: Washington, DC, 1982.


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C Dating of an Iron Bloom

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Frobisher c o l l e c t i o n s : nothing could be found, d e s p i t e h i s exhaustive i n q u i r y . His f r u s t r a t i o n permeates h i s account o f the search [11]. His f i r s t attempt t o e l i c i t i n f o r m a t i o n from the Smithsonian brought the response (August 12, 1935) t h a t "... a very c a r e f u l search has been made o f our records but we f i n d no evidence t h a t any r e l i c s o f t h i s g a l l a n t e x p l o r e r were ever deposited here." Since t h i s response d i d not agree w i t h t h e known evidence, Stefansson t r i e d t h e Smithsonian again. This time (August 28, 1935) the r e p l y came t h a t ... a very thorough and c a r e f u l search has been made o f our records and o f the specimens r e c e i v e d by us from t h e Polaris [ t h e name o f H a l l ' s s h i p ] E x p e d i t i o n but u n f o r t u n a t e l y without any success so f a r as F r o b i s h e r r e l i c s are concerned. On one l i s t there i s mention o f a s i n g l e specimen as f o l l o w s : "Iron bloom, obtained from Countess o f Warwick Sound where i t was made by Frobisher i n 1578, searching f o r g o l d . " A c a r e f u l examination o f the specimens, however, f a i l s t o reveal any o b j e c t answering to t h i s d e s c r i p t i o n . In f a c t the accession record o f the U. S. National Museum (#2157) contains a f u l l l i s t i n g o f the H a l l o b j e c t s as they were returned from loan s t a t u s a t t h e I n t e r n a t i o n a l E x h i b i t i o n held a t P h i l a d e l p h i a t o c e l e b r a t e the c e n t e n n i a l o f American independence. Why they could not be l o c a t e d i n 1935 i s unknown, but i n 1950, i n gathering data f o r Remington K e l l o g g , D i r e c t o r o f the U. S. National Museum, f o r a response t o Mrs. H. S. M a r l e t t who had r a i s e d t h e same questions Stefansson had e a r l i e r broached, t h e c u r a t o r o f t h e D i v i s i o n o f Ethnology, H. W. K r i e g e r , i n a memo to Frank M. S e t z l e r , head c u r a t o r , Department o f Anthropology, dated March 17, 1950, reported t h a t the "Iron Bloom" (Cat.#10,291) "was r e c e n t l y l o c a t e d by Mr. R. S i r l o u i s i n the G a l l e r y storage o f the Department o f H i s t o r y " and " r e s p e c t f u l l y requested" that permission be given t o t r a n s f e r t h e c a t a l o g card d e s c r i b i n g i t to the Department o f H i s t o r y . As f o r the " R e l i c s o f Frobisher's Voyage" (Cat.#14,247) K r i e g e r opined t h a t i t o f f e r e d "a problem not r e a d i l y solved." " I f the pieces o f c o a l , fragments o f i r o n , g l a s s and p o t t e r y were not numbered i n d i v i d u a l l y , " he went on " i t i s u n l i k e l y t h a t they w i l l be found." K r i e g e r concluded h i s memo by noting t h a t " P r a c t i c a l l y a l l mistakes t h a t a museum could make i n a c c e s s i o n i n g , cataloguing, preservation, recording, c l a s s i f i c a t i o n , and correspondence a r e i l l u s t r a t e d i n our connec t i o n w i t h the Charles F. H a l l c o l l e c t i o n s . " U n f o r t u n a t e l y , K r i e g e r , i n a memo o f January 26, 1953 t o Dr. K e l l o g g through Mr. S e t z l e r (correspondence F i l e 197929) requested a condemnation committee t o dispose of objects "fragmentary o r broken beyond r e p a i r ; i n p a r t , undocumented and



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u n i d e n t i f i a b l e . " He noted t h a t "a considerable number of these specimens were c o l l e c t e d by e x p l o r i n g expeditions to the A r c t i c . Although the expeditions are h i s t o r i c a l , the r e l i c s submitted f o r d i s p o s a l c o n s i s t of driftwood fragments, stone pebbles, s h e l l s and animal bones. On i n q u i r y , i t was found t h a t these items are not wanted e i t h e r by H i s t o r y , Geology, Zoology or Anthropology." A condemnation committee c h a i r e d by Mr. S e t z l e r , with Krieger and David H. Dunkle as members, recommended d i s p o s a l of a v a r i e t y of objects i n a memo of March 27, 1953 to Dr. K e l l o g g , who approved the condemnation on March 30. Among the items discarded from the H a l l c o l l e c t i o n were "minerals," "shot," "cross bar?," " q u a r t z i t e , " " i r o n p y r i t e s , " and "quartz rock," as w e l l as "pebbles," "sand stone rock," "one l o t sea s h e l l s , " " d r i f t wood," "plumbago used by n a t i v e s , " and " r i b of spotted s e a l . " On h i s a r r i v a l a t the Smithsonian i n 1958 as c u r a t o r of the D i v i s i o n of P o l i t i c a l H i s t o r y , Wi1 comb Washburn i n h e r i t e d some of the c o l l e c t i o n s of the o l d Department of H i s t o r y , which i n t u r n had broken o f f from the D i v i s i o n of Ethnology. Because of h i s i n t e r e s t i n e x p l o r a t i o n and d i s c o v e r y , he was e x c i t e d when i n 1964 he discovered the i r o n bloom t h a t i s the subject of t h i s paper i n a remote p a r t of the h i s t o r y storage area i n the A r t s and I n d u s t r i e s B u i l d i n g (Figure 1). The o b j e c t was not catalogued i n h i s D i v i s i o n , but he f i l e d a request through the D i v i s i o n of Naval H i s t o r y , to the new a n a l y t i c a l and conservation laboratory to analyze the metal and determine i t s age. He hoped to be able to present t e c h n i c a l evidence of the age of the s p e c i men i n the course of a paper e n t i t l e d "The O r i e n t a l Purpose of the A r c t i c Navigations" t h a t he was scheduled to d e l i v e r i n August 1970 i n Moscow, at a meeting of the I n t e r n a t i o n a l Commission of Maritime H i s t o r y during the X I I I I n t e r n a t i o n a l Congress of H i s t o r i c a l Sciences. Because the information was not a v a i l a b l e by the time he l e f t f o r Moscow, he was able to report i n h i s paper, which was p r i n t e d i n Etudes D'Histoire Maritime, ( P a r i s , 1970), pp. 132-146, merely t h a t the Smithsonian I n s t i t u t i o n was working on the dating of the specimen. The discovery of unmistakeable V i k i n g remains at L'Anse aux Meadows by the Ingstads i n 1960 had r e o r i e n t e d people's t h i n k i n g concerning the r e a l i t y of a V i k i n g presence i n the New World, and i n 1967 Dr. Chauncey Loomis reported i n an i n t e r n a l Smithsonian memorandum t h a t "Dr. Mel v i n H. Jackson has suggested t h a t the bloom might not be a Frobisher r e l i c - s i n c e there was no mention of a smelter i n any of the extensive Frobisher w r i t t e n records" [17]. We should note, however, t h a t the Rawson-MacMillan expedi t i o n i n 1927 d i d report "the r u i n s of two furnaces, w i t h evidence of o l d f i r e s and c l i n k e r s i n them." [13, p. 32] Perhaps t h i s was where the " r e f i n e r s " c a r r i e d out t h e i r t e s t s on the ore, mentioned e a r l i e r i n connection w i t h the c r u c i b l e streaked w i t h s l a g . With the Frobisher bloom once more i n hand, the problem of dating i t became paramount. Owing to the circumstances of i t s



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Figure 1. An iron bloom in the collection of the Department of Naval History, National Museum of American History, Smithsonian Institution (Cat. No. 49459). The bloom weighs approximately 17 lb, after sampling, and is approximately 18 cm in diameter on the base as shown. (Smithsonian Institution negative No. 74836.)


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discovery by C. F. H a l l , there seemed t o be l i t t l e p o s s i b i l i t y of carbon 14 d a t i n g by s t r a t i g r a p h i e a r c h a e o l o g i c a l a s s o c i a t i o n w i t h , f o r example, c h a r c o a l , nor would the s i g n i f i c a n c e of such a date have been very apparent. But i n the I960 s Dr. N. Van der Merwe had p e r f e c t e d a technique f o r the carbon 14 d a t i n g of i r o n i t s e l f , through d a t i n g the carbon e x t r a c t e d from the metal [18]. I t i s important to r e s t a t e the obvious; t h a t the date obtained i s t h a t of the carbon content of the i r o n and not n e c e s s a r i l y t h a t of the smelting process. For example, i f coke were used t o smelt the i r o n , the carbon would be q u i t e i n a c t i v e . I f a very o l d timber were converted to c h a r c o a l , the carbon taken up would r e f l e c t t h a t age. Likewise any admixture of limestone e t c . , c o n t a i n i n g dead i n o r g a n i c carbon might make the age greater. Van der Merwe had, however, obtained r e l i a b l e dates on several pieces of i r o n of known age, i n c l u d i n g bloomery i r o n from Roman times [18]. Moreover, i t i s w e l l known t h a t i n e a r l y m e t a l l u r g y , bloom i r o n makers o r d i n a r i l y converted l o c a l l y - c u t wood to charcoal f o r use i n s m e l t i n g , and t h i s encouraged one t o t h i n k t h a t a carbon 14 measurement o f the Frobisher bloom could y i e l d useful informa t i o n [19]. Bloomery i r o n i s c h a r a c t e r i z e d , however, by very low carbon content (Table 1) and i f one wished to c a r r y out a conventional carbon 14 d a t i n g , consumption of the e n t i r e 20 l b . bloom would have y i e l d e d only 4 or 5 grams of carbon, which i s b a r e l y enough. For t h i s reason, the C o n s e r v a t i o n - A n a l y t i c a l Laboratory of the Smithsonian I n s t i t u t i o n sponsored the development of the micro-scale d a t i n g procedures a t Brookhaven Laboratory already r e f e r r e d to above [9,10]. The a c t u a l measurement proceeded as f o l l o w s : Approximately 1 kilogram of the F r o b i s h e r bloom was m i l l e d i n t o powder. Two separate i r o n samples, d i f f e r i n g only i n t h e i r pretreatment, were taken. The f i r s t sample of 40 grams was washed w i t h three 100 mL p o r t i o n s of 0.1 N HC1 by shaking v i g o r o u s l y i n a poly ethylene b o t t l e , a f t e r which the sample was washed w i t h d i s t i l l e d water i n the same manner and d r i e d i j i vacuo a t room temperature. A second sample of 40 g was s i m i l a r l y t r e a t e d except t h a t the washing w i t h 0.1 N HC1 was preceded by three washes w i t h 0.1 Ν NaOH. As check samples, specimens of c a s t i r o n from Redding Furnace (1761 A.D.) [17,21] and from Saugus (1648-1678 A.D.) [21] were a l s o measured. Both of these were bulk samples and encrusted w i t h c o r r o s i o n . The c o r r o s i o n was removed t o reveal b r i g h t metal w i t h a small hand v i b r a t i n g t o o l . Samples s u i t a b l e f o r combustion were taken by m i l l i n g w i t h a new t o o l which had been cleaned w i t h hexane. A d e t a i l e d procedure f o r combustion, p u r i f i c a t i o n , and f i l l ing of the small gas p r o p o r t i o n a l counters may be obtained from the Brookhaven authors. Since the apparatus f o r combustion had a maximum c a p a c i t y of 10 grams i t was necessary t o burn three samples of F r o b i s h e r i r o n i n order to get enough carbon d i o x i d e to f i l l the counter. The carbon d i o x i d e from the three samples was


1


Currie; Nuclear and Chemical Dating Techniques ACS Symposium Series; American Chemical Society: Washington, DC, 1982. C-8

C-22

C-12

C-5

Counter d number

10.77

1 4

C date,

t^

2

= 5730 y e a r s , no c a l i b r a t i o n

P r e t r e a t e d with 0.1

P r e t r e a t e d with 0.1

9

h

Ν HC1.

Ν HC1 and 0.1

Ν NaOH.

83/57 Carbon analy

16651145 combined.

Cpd = counts per day.

f o r B r i s t l e c o n e pine.

^ F i r s t number, sample, second number, o x a l i c a c i d standard.

Conventional

counter.

C - 5 , C-22 and C-8 are 5 c c . counters, C-12 i s a 7.5 c c .

C.

d

1 3

These count rates already include the background and i s o t o p i c c o r r e c t i o n s .

of

2

285+145

79/69 14811144 4691144

10.51

72.111.0

67.711.1

103/81 11581107

97/114

Counted*

Days

7921107

12711133

Date, AD

e

16.16

6791133

B.P.

Carbon

10.34

14, C years

mg.

Age

73.611.6

51.111.1

i n cpd

Background

c

We thank Mr. A. P. Irsa f o r the mass spectrometric determination

b

15.53±0.19 16.07±0.21

14.78±0.19 15.64±0.19

-26.1

-24.9

14.69+0.15 1 6 . 1 6 ± 0 . 1 3

14.44±0.19 15.68±0.15

-24.2

-23.6

a c i d χ 0.95

Sample

PDB per mil

in

NBS O x a l i c

C ref.

c

to

13

cpd/mg-C

14,C A c t i v i t y

Counting Data on Carbon 14 Extracted from Ancient Iron Specimens.

Because of the s i z e l i m i t a t i o n s , three i r o n samples were separately combusted and the C 0 ses f o r the three subsamples are separately l i s t e d .

3.98

Redding Furnace

a

3.73

.049 .061 .048

.051 .062 .127

Saugus

(combined)**

Frobisher

(combined)**

Frobisher

Sample

Percent _a Carbon

Table 1.



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then combined before p u r i f i c a t i o n . Both Redding Furnace and Saugus contained such ample carbon t h a t only one combustion sample was r e q u i r e d . A f t e r the counting was completed, i s o t o p i c carbon abundances were measured so t h a t a p p r o p r i a t e c o r r e c t i o n s might be a p p l i e d . The d e t a i l e d a n a l y t i c a l and counting data f o r the F r o b i s h e r i r o n samples are presented i n Table 1, along w i t h the summarized r e s u l t s f o r Saugus and Redding i r o n . The approximate weight of the F r o b i s h e r bloom i s nineteen pounds; t h i s may be compared t o the weights of E n g l i s h i r o n blooms reported by T y l e c o t e , 1962 [22]. Up u n t i l the f o u r t e e n t h century the weight of blooms d i d not exceed about t h i r t y pounds; however, w i t h the i n t r o d u c t i o n of water-power i n the f o u r t e e n t h century, t h i s increased to one to two hundred pounds. Neverthe l e s s , i f a bloom were produced under p r i m i t i v e c o n d i t i o n s , i t i s l i k e l y t h a t i t c o u l d be s m a l l e r than those reported by Tylecote f o r the s i x t e e n t h century. This may have been the case i f the F r o b i s h e r bloom was produced i n B a f f i n I s l a n d . The phosphorus c o n c e n t r a t i o n i n the metal of the bloom i s a l s o of i n t e r e s t . Tylecote r e p o r t s on the changes i n phosphorus concen t r a t i o n s t h a t the highest concentrations i n E n g l i s h blooms were during the p e r i o d of about 800-1100 A.D. By the s i x t e e n t h century, the phosphorus c o n c e n t r a t i o n i n the i r o n dropped to below 0.1 percent and t h i s i s a t t r i b u t e d to a search i n the Later Medieval p e r i o d f o r ores c o n t a i n i n g lower phosphorus. We have analyzed a s e c t i o n of the F r o b i s h e r bloom using the e l e c t r o n microprobe and have found an average c o n c e n t r a t i o n of phosphorus i n the i r o n phase of the bloom of approximately 0.6 percent. This i n f o r m a t i o n again suggests t h a t the bloom i s not c h a r a c t e r i s t i c of E n g l i s h blooms of the s i x t e e n t h century. I t i s i n t e r e s t i n g to compare the F r o b i s h e r bloom to an i r o n r i v e t , LaM 60, excavated a t L'Anse aux Meadows, Newfoundland by Anne S t i n e Ingstad and discussed by Anna M. Rosenquist [23]. Although the r i v e t was examined w i t h a microprobe, the c o n c e n t r a t i o n of phosphorus was not reported t o have been measured; however, the author s t a t e s from m e t a l l o g r a p h i c examination t h a t the r i v e t "appears t o have been forged from a p i e c e of f e r r i t i c s t e e l w i t h a carbon content of l e s s than 0.2 percent c o n t a i n i n g phosphorus." Further compari son of the F r o b i s h e r bloom and the r i v e t from L'Anse aux Meadows could be i n f o r m a t i v e . The average date of the carbon i n the F r o b i s h e r bloom, 1214 A.D. ± 175, i n the middle of the Norse occupation of Greenland, r a i s e s the question of i t s p o s s i b l e Norse r e l a t i o n s h i p . The s i t e a t L'Anse aux Meadows has been dated t o ca. 1000 A.D. [ 2 3 ] , and Norse a r t i f a c t s and a r t i f a c t s made from Norse m a t e r i a l s , such as i r o n , copper, bronze, European oak, and t e x t i l e s have been found i n s e v e r a l Dorset and Thule s i t e s of the 12-13th Centuries [24-26]. One of these f i n d s i s a carved wooden f i g u r i n e recovered from a Thule c u l t u r e s i t e on the south coast of B a f f i n I s l a n d near Lake Harbor [27]. The f i g u r i n e , from a house whose a r t i f a c t assemblage dates s t y l i s t i c a l l y to the 12-13th C e n t u r i e s , appears



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to be a Thule Eskimo p o r t r a y a l of a Norseman encountered, perhaps, i n the l o c a l area. Since Norse voyaging along t h i s coast would r e q u i r e f a m i l i a r i t y w i t h F r o b i s h e r Bay, i t i s p o s s i b l e t h a t they were i n Countess of Warwick Sound around 1200 A.D. While t h i s makes sense i n terms of the bloom's s i z e and composi t i o n , i t s d i s c o v e r y i n s i d e F r o b i s h e r ' s "ships t r e n c h " , where r e p a i r s t o h i s v e s s e l s would have r e q u i r e d the use of i r o n , p o i n t s s t r o n g l y toward a F r o b i s h e r o r i g i n . I t seems u n l i k e l y t h a t t h i s bloom, and p o s s i b l y the others found by H a l l nearby, were a l l recovered by F r o b i s h e r ' s men from Norse s i t e s . Rather, i t seems more l i k e l y t h a t these blooms were produced l o c a l l y by F r o b i s h e r ' s men under p r i m i t i v e f i e l d c o n d i t i o n s t h a t might have c o n t r i b u t e d t o the d i f f e r e n c e s noted from contemporary European blooms. Such an i n t e r p r e t a t i o n , however, would r e q u i r e e x p l a n a t i o n of the e a r l y date. I f the Bloom was produced a t F r o b i s h e r ' s s i t e , as suggested by the s l a g and c r u c i b l e , e a r l y carbon c o u l d have been introduced i f d r i f t w o o d was the source of f u e l . Today, F r o b i s h e r Bay and nearby regions of southeastern B a f f i n I s l a n d do not have t r e e s o r woody p l a n t s s u i t a b l e f o r f u e l i n g a smelter, and there i s no i n d i c a t i o n from palynology t h a t l i v i n g wood was more p r e v a l e n t i n the 13th Century [28]. However, d r i f t w o o d , which i s a v a i l a b l e today and c e r t a i n l y was a l s o i n the p a s t , could have served t h i s purpose admirably. Driftwood might reach F r o b i s h e r Bay from Hudson Bay or northern Quebec, but p r e v a i l i n g winds and c u r r e n t s c a r r y most of t h i s wood south along Labrador. Modern and f o s s i l d r i f t w o o d c o l l e c t e d from the i s l a n d s of the Eastern A r c t i c and Greenland comes p r i m a r i l y from S i b e r i a n sources v i a the slow A r c t i c Ocean c i r c u l a t i o n and subsequent t r a n s p o r t south through the a r c t i c i s l a n d s or by the East Greenland, Irminger, and East B a f f i n Current. The time span of such a d r i f t i s unknown, but w i t h i n t e r r u p t i o n s and strandings i t c o u l d take hundreds of years before a specimen came to r e s t i n East B a f f i n . Modern d r i f t w o o d samples c o l l e c t e d from Jones Sound i n southern Ellesmere I s l a n d have been dated between 30-250 years [29] w h i l e fossil driftwood from r a i s e d beaches here produced dates thousands of years o l d . Both modern and f o s s i l d r i f t w o o d and contemporary European wood f u e l s would have been a v a i l a b l e t o F r o b i s h e r ' s men i n Countess of Warwick Sound. These and other f a c t o r s of a m e t a l l u r g i c a l and a r c h a e o l o g i c a l nature must be considered i n i n t e r p r e t i n g the date obtained from the F r o b i s h e r bloom. I t would be e s p e c i a l l y u s e f u l t o compare t h i s specimen w i t h samples of Norse i r o n and blooms from Greenland and Europe. Nevertheless, the f a c t t h a t the date i s a t l e a s t two standard d e v i a t i o n s removed from the date of the F r o b i s h e r voyages i s of i n t e r e s t . Unless the carbon was not contemporary w i t h the s m e l t i n g of the i r o n , there i s only a small chance t h a t the bloom was "made by F r o b i s h e r i n 1578, searching f o r gold".


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The research performed a t Brookhaven National Laboratory was under c o n t r a c t w i t h the U. S. Department o f Energy and was supported by its D i v i s i o n o f B a s i c Energy Sciences.


References [1] Muller, R. Α., Science, 1977, 196, 489. [2] Bennett, C. L., Beukens, R. P., Clover, M. R., Gove, Η. Ε., Liebert, R. Β., Litherland, Α. Ε., Purser, Κ. Η., Sondheim, W. Ε., Science, 1977, 198, 508. [3] Nelson, D. Ε., Korteling, R. G., Stott, W. R., Science, 1977, 198, 507. [4] Muller, R. Α., Stephenson, E. J., Mast, T. S., Science, 1978, 201, 347. [5] Bennett, C. L., Beukens, R. P., Clover, M. R., Elmore, D., Gove, Η. Ε., Kilius, L., Litherland, Α. Ε., Purser, Κ. Η., Science, 1978, 201, 345. [6] Muller, R. Α., Physics Today, Feb. 1979, 23. [7] Gove, Η. Ε., ed., Proceedings of the First Conference on Radiocarbon Dating with Accelerators, University of Rochester, 1978. [8] Stuiver, Μ., Science, 1978, 202, 881. [9] Harbottle, G., Sayre, Ε. V., Stoenner, R. W., Science, 1979, 206, 683. [10] Contract No. FC-5-53083 between the Smithsonian Institution Conservation-Analytical Laboratory (Dr. R. M. Organ) and Brookhaven National Laboratory, dated 6/24/75. [11] Stefansson, Vilhjalmur, The Three Voyages of Martin Frobisher, The Argonaut Press, London 1938, See Introduction and Appendix 9. [12] Mori son, Samuel Eliot, The European Discovery of North America: The Northern Voyages AD 500-1600, 1971 Oxford Press, New York. [13] Roy, Sharat Κ., Geological Series of (the) Field Museum of Natural History 1937, VII (2) 21. [14] Fox-Bourne, H. R., English Seamen under the Tudors, 2 Vols. 1868, London. [15] Hall, Charles Francis, Life with the Esquimaux, Sampson Low, Son, and Marston, London, 1865. [16] (No author), Science, 1927, 66, 295-6. [17] Conservation-Analytical Laboratory Requisition Folder Number 0019. [18] Van der Merwe, Nikolaas, J . , The Carbon 14 Dating of Iron, 1969, University of Chicago Press. [19] Shubert, H. R., History of the British Iron and Steel Indus try from ca. 450 BC to 1775 AD, 1957, London.



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[20] The Redding Furnace specimen is a dated stoveplate which was provided through the courtesy of Mrs. Paul Sias, Director, Mercer Museum, Doylestown, Pa. [21] The origin of the Saugus specimen is by courtesy of Mr. W. Glen Gray, Park Manager, Saugus Iron Works, National Historic Site. [22] Tylecote, R. F., Metallurgy in Archaeology, London, pp. 296298, 1962. [23] Ingstad, Anne Stine, The Discovery of a Norse Settlement in America, Universitetsforlaget, Oslo, p. 381, 1977. [24] Harp, Elmer, Jr., A late Dorset amulet from southeastern Hudson Bay, Folk, 16-17, 33-44 (1974/75). [25] MacCartney, A. P. and Mack, D. J., Iron utilization by Thule Eskimos of Central Canada, American Antiquity, 38(3), 328-338 (1973). [26] Schledermann, Peter, Notes on Norse finds from the east coast of Ellesmere Island, N.W.T. Arctic, 33(3), 454-463 (1980). [27] Sabo, Deborah and Sabo III, George, A possible Thule carving of a Viking from Baffin Island, N.W.T., Canadian Journal of Archaeology, 2, 33-42 (1978). [28] Short, Susan and Andrews, John T., Palynology of six Middle and Late Holocene peat sections, Baffin Island, Geographie Physique et Quaternaire, 34(1), 61-75 (1980). [29] Blake, Weston, Jr., Radiocarbon age determinations and postglacial emergence at Cape Storm, southern Ellesmere Island, Arctic Canada, Geografiska Annaler, 57, Ser. A, 1-2, 1-71 (1975). RECEIVED August 21, 1981.


The Carbon-14 Dating of an Iron Bloom Associated with the Voyages

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