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The discharge of saline groundwater results in the formation of sodic soil scalds in irrigated, dryland and urban environments of southeastern Australia. Sodic soils are dispersive, and this leads to soil erosion and a loss in agricultural productive capacity. These sodic soils commonly show polygonal cracking and pressure ridges indicating the presence of swelling clays. Infrared spectroscopy of scald surfaces and XRD (X-ray diffraction) analyses of the clay fractions of the sodic soils show the presence of amorphous clays, smectite, illite or mixed smectite/illite layer clays. Non-salinised soils adjacent to the salt scalds are commonly predominantly kaolinitic. SEM images and normative EDS mineral analyses of the clay fractions of these soils show that crystalline particles, predominantly of kaolinite, are progressively replaced by poorly crystalline smectite, illite and amorphous material. Normative mineral analyses determined from the bulk soil composition, based on a derived composition of submicron...

A novel approach for using field spectrometry for determining both the mineralogy and the lithology of drill core pulps (powders) is developed and evaluated. The methodology is developed using material from a single drillhole through a mineralized sequence of rocks from central New South Wales. Mineral library spectra are used in linear unmixing routines to determine the mineral abundances in drill core pulps that represent between 1 m and 3 m of core. Comparison with X-Ray Diffraction (XRD) analyses shows that for most major constituents, spectrometry provides an estimate of quantitative mineralogy that is as reliable as that provided by XRD. Confusion between the absorption features of calcite and those of chlorite causes the calcite contents determined by spectrometry to be unreliable. Convex geometry is used to recognize the spectra of those samples that are extreme and are representative of unique lithologies. Linear unmixing is used to determine the abundance of these lithologies in each drillhole sample and these abundances are used to interpret the geology of the drillhole. The interpreted geology agrees well with conventional drillhole logs of the visible geology and photographs of the split core. The methods developed provide a quick and cost-effective way of determining the lithology and alteration mineralogy of drill core pulps.

At the time (1542) when Jean Rotz presented Henry VIII with a variation compass, and an accompanying treatise1 on its making and use, the question of magnetic variation was an acute one. It formed part of a wider controversy concerning the general validity of the sea-chart which had been raised among seamen. As to this, Dr. Pedro Nuñez, writing a treatise in 1537 addressed to his friend and pupil the Infante Dom Luys of Portugal, said that there were skilled pilots who derided the chart and declared it to be ‘a mais falsa causa do mundo’—the falsest thing in the world. Hastening to its defence, Nuñez dealt at length with the navigating errors introduced by ignoring the convergence of the meridians, and showed besides that a rhumb, or line of constant bearing, was a spiral curve on the globe. He dealt only incidentally with the variation of the compass needle and how to measure it, and this may explain why Rotz made this second source of error his main theme. The parallel N.–S. lines and E.–W. lines of the compass roses making a rectangular net on the chart are completely misleading, he says, for only the ‘diametral line’ (agonic line, line of no variation) actually runs through the poles of the world, the others lie at angles one with the other according to the magnetic variation.

To compare British Pakistani parents' and their relatives' attitudes to prenatal testing (PND) and termination of pregnancy (TOP) for a range of conditions.A total of 222 British Pakistani participants: 117 parents of children with a child with a genetic condition (52 fathers and 65 mothers) and 103 of their relatives (51 males and 52 females) completed a structured questionnaire about their attitudes toward PND and TOP for 30 different conditions.Parents were more accepting of PND (P0.001) and TOP (P0.001) than their relatives for most of the conditions. Male relatives were consistently least interested in PND and TOP, except for conditions at the serious end of the continuum, where over 90% would opt for PND for quadriplegia and anencephaly, and over 60% would opt for TOP for these conditions.The lower level of interest in PND and TOP in relatives, particularly men, may be due to lack of information disseminated by parents about their child's recessive inheritance and its implications for relatives, resulting in poor understanding of genetic risk. These findings highlight the need for the provision of proactive genetic counselling to raise awareness of genetic risk and facilitate informed reproductive decision-making in at-risk relatives.

The case notes of all children admitted during the preceding five years for observation with painful hips (509 patients) were analysed to determine significant diagnostic factors and thus to design and admission policy. Most orthopaedic disorders (62 patients) were apparent on the initial radiographs, with the important exception of osteomyelitis/septic arthritis (21 patients). The remaining 426 patients were diagnosed by exclusion as having an irritable hip. The latter two groups were similar with respect to age, sex, and duration and nature of symptoms. A number of clinical features and laboratory investigations recorded within 12 hours of admission, however, were shown to have significant discriminative value. These were severe spasm, tenderness, pyrexia > or = 38 degrees C, and an erythrocyte sedimentation rate of > or = 20 mm/hour (the white cell count was not significant). Combination of any two of these produced a specificity and sensitivity for sepsis of 91% and 95% respectively (95% confidence interval 0.64 to 0.97). A protocol designed from this data analysis is now being tested and is expected to result in a significant reduction in admission rates.

By convention, most indwelling urethral catheters are removed in the morning. The authors carried out a randomized prospective study of 101 patients with postoperative urethral catheters and compared midnight removal with the more usual practice of morning removal. Patients were randomized into two groups: group A (n=46) had their catheters removed at 6:00 am and group B (n=49) had their catheters removed at midnight. Six patients were excluded from the study (1 patient on distigmine and 5 with preexisting urinary tract infections). The groups were comparable in age, use of night sedation, operative procedures and incidence of postoperative urinary tract infections. Patients in group B passed urine a median of 1 hour 40 minutes earlier, with a median volume 175 ml greater than group A (P=0.012 and

We examined 67 different mutations in 16 different amplicons in a comparison of mutation detection by fluorescent single strand conformation polymorphism (F-SSCP) and by denaturing HPLC (DHPLC). F-SSCP was used to analyze fluorescent amplicons with internal size standards and automated fragment analysis (GeneScan, PE Applied Biosystems, Foster City, CA). In DHPLC, unlabelled amplicons were analyzed by reverse phase HPLC with fragment detection by absorbance at 260nm. Both methods had high sensitivity (95-100%) and specificity (100%). Overall, F-SSCP with external temperature control was the more sensitive method, but DHPLC was particularly useful for the rapid analysis of novel fragments.

Cleavage-based methods of mutation detection offer a simple and intuitive means to detect and in most cases locate mutations within DNA fragment sizes ranging from 500 to 1500 bases. Their main advantages as a presequencing screening technology when scanning for unknown mutations is the potential to increase throughput by multiplexing. Combined with lower reagent costs per sample, mutation scanning methods offer significant advantages over currently available sequencing techniques and are likely to be of increasing importance as genomic sequence data becomes more readily available. Although enzymatic methods offer the advantages of simpler and less hazardous protocols, at present the most robust cleavage methods are based around chemical methods.

The properties of a steady-state, dc discharge multidipole ion source have been investigated. The plasma density in the source depends on the magnet geometries, the discharge voltage, and the bias voltage on the first extraction grid. Different schemes to reduce the loss of ions to the chamber wall are described. Hydrogen ion species in the extracted beam are studied by a mass analyzer.

SynopsisDNA was extracted from the brains of patients with Alzheimer-type dementia, schizophrenia, Huntington's chorea and from patients without neurological disease, and examined for the presence of herpes simplex virus type 1 and human cytomegalovirus sequences. By selecting cloned virus DNA fragments which do not hybridize to normal human DNA we were able to achieve a detection level assessed on reconstruction experiments of 1 virus genome per 50 cells. Screening at such sensitivity did not detect virus sequences in the higher CNS, except in cases of encephalitis or immunosuppression. We conclude that, at this level of sensitivity, these viruses cannot be regarded as normal residents of the higher CNS, and at the time of death they do not appear to be associated with these neuropsychiatric conditions.

The Vinland Map, published with considerable publicity as ‘the most exciting cartographic discovery of the century’ by Yale University Press in 1965, has now, on the evidence of spectographic analysis by Walter McCrone Associates of Chicago, been virtually proved to be a modern forgery. The details, which have appeared widely in the press and were the subject of a meeting at the Royal Geographical Society on 4 February 1974, need not concern us here. The interest in Professor Taylor's paper written in 1963 well before the map's publication, is that working from measurements on a facsimile reproduction and with her own unrivalled knowledge of early cartography she was able to establish, at any rate to her own satisfaction, that the Old Map, as she calls it throughout, was a fake. She was the first scholar to cast serious doubt on the map's authenticity, and needless to say her views were hotly contested.

Viruses have individual and characteristic isoelectric points and for poliovirus there was good evidence for a correlation between one of these and sensitivity to chlorine. However, in the presence of chlorine dioxide, bromine chloride and iodine the behaviour of poliovirus and f2 coliphage was similar and not apparently influenced by the isoelectric point.

A male child, maintained in a controlled environment, was monitored each month for bacteria, yeasts, and filamentous fungi recovered from the mouth, nasal passages, feces, and nine body surface sites. Three natural microbial categories became apparent. Incident microorganisms were recovered from within the isolator but did not establish permanent residence. Of the 53 incident types isolated, 20 were filamentous fungi and 4 were yeasts. Some genera, such as Fusobacterium, Lactobacillus, Neisseria, and Rothia, which were commonly found in the reference group, did not become permanent inhabitants. Transient microorganisms were repeatedly recovered but could not be demonstrated within the isolated environment at the end of the study. The loss of only a few of the 19 transient species could be associated with antimicrobial therapy. Permanent microorganisms consisted of Pencillium citrinum and 17 bacterial types, of which alpha-hemolytic streptococci, Staphylococcus edpidermidis subgroups II and V, Micrococcus groups 1 and 2, Clostridium bifermentans, and Propionibacterium acnes were recovered throughout the entire 9 years of the study. The number of CFUs recovered from each sample type was generally not unlike that from the reference group of healthy male adults. Also, the number of different aerobic species recovered from the feces was within the normal range of that of the reference group. In contrast, the number of different species recovered from all other samples was less than that commonly found in the reference group.

The composition and melting points of the bromine adducts of pyridinium bromide have been determined. Differential scanning calorimetry has been found to be particularly well suited to this type of phase study because it uses small, enclosed samples and responds rapidly to small heat changes. The adducts are described in terms of stoichiometric mixtures of pyridinium bromide and pyridinium tribromide, or in terms of a general formula PyHBr(Br2)n where n equals 1/3, 1/2, 2/3, 1, 3, 6, 18. When pyridinium bromide is allowed to pick up bromine isothermally in an apparatus for thermogravimetric analysis it does so in a stepwise manner with a plateau for each of the above adducts plus one with n equal to 3/2. This provides valuable confirmation of the compositions of adducts deduced from conventional phase diagrams.

Detailed mapping of Eocene to early Oligocene basalts on the Monaro has enabled the production of topographic maps of the pre‐basaltic topography in the region. Comparison of the sub‐basaltic and present topography shows there has only been minimal change in topography and drainage patterns during the Cainozoic. This indicates that in the Monaro, either no significant uplift has occurred during the majority of the Cainozoic, or that the streams do not respond rapidly to external changes of base level.

Mineralized veins at Major's Creek consist of preponderant quartz and carbonate gangue with gold, Au-Ag tellurides and base metal sulphides within silicified and sericitized dykes or granodiorite of the Braidwood Granite. Fluid inclusion studies indicate deposition throughout the range 350–80°C by low salinity fluids. Significant Au-Ag telluride mineralization took place at a temperature of about 155°C. Mineral deposition was due to the separation of a liquid CO2 phase from an originally CO2-rich aqueous fluid. Observed argillic alteration is a consequence of acid leaching above the boiling zone. Mineralization is epithermal in character and probably formed during the existence of a hydrothermal convective system. A relationship with similar epithermal gold deposits in the adjacent Eden-Yalwal Rift zone is inferred.

The biosynthesis of thymidylate in the yeast Saccharomyces cerevisiae can be inhibited by antifolate drugs. We have found that antifolate treatment enhances the formation of leucine prototrophs in a haploid strain of yeast carrying, on the same chromosome, two different mutant leu2 alleles separated by Escherichia coli plasmid sequences. That this effect is a consequence of thymine nucleotide depletion was verified by the finding that provision of exogenous thymidylate eliminates the increased production of Leu+ colonies. DNA hybridization analysis revealed that recombination, including reciprocal exchange, gene conversion and unequal sister-chromatid crossing over, between the duplicated genes gave rise to the induced Leu+ segregants. Although gene conversion unaccompanied by crossing over was responsible for the major fraction of leucine prototrophs, events involving reciprocal exchange exhibited the largest increase in frequency. These data show that recombination is induced between directly repeated DNA sequences under conditions of thymine nucleotide depletion. In addition, the results of this and previous studies are consistent with the possibility that inhibition of thymidylate biosynthesis in yeast may create a metabolic condition that provokes all forms of mitotic recombination.

1. Journal de bord de Juan de la Cosa, second de Christophe Colomb. Presenté et commenté par Ignacio Olagué. Paris, 1957, 870 frs.2. The Journal of Christopher Columbus. Translated by Cecil Jane, revised and annotated by L. A. Vigneras with an appendix by R. A. Skelton. Anthony Blond and The Orion Press, London, 1960, 45s.Writing an Introduction to the Four Voyages of Columbus over thirty years ago, the late Cecil Jane remarked: ‘It might with justice be added that no event of such moment can ever occur again, unless, perhaps the tracts of space be bridged and communication established between the Earth and her sister planets.’ The fact that we are on the very eve of placing a man in the Moon should enable us to appreciate more justly the various ways in which, during the late fifteenth century, different people reacted to the daring proposal of Columbus to sail west to Asia.

The term ‘dead reckoning’, so the Admiralty Navigation Manual (1938) says, is a corruption of the old ‘ded-uced reckoning’ or ‘position by account’, and is used to cover all positions that are obtained from ‘the course the ship steers and her speed through the water, and from no other factors.’ (The last italics are ours.) Had Master William Borough, Chief Pilot of the Muscovy Company, and presently to be appointed to Queen Elizabeth's Navy Board, come across this definition, he would have picked a two-fold quarrel with their present Lordships at Whitehall. For his use and explanation of the term is the earliest of which we have knowledge, although it does not appear even then to have been new.

In a previous article in this Journal mention was made of an unexamined manuscript by Hariot belonging to the Petworth Collection entitled The Doctrine of Nauticall Triangles Compendious, which promised to be of interest to navigators. When Lord Leconfield, the owner of the Collection, heard of this he very kindly himself brought this manuscript to the British Museum for study there, and meanwhile Dr. Shirley of the United States, who is at work on other aspects of Hariot's life, sent over from America a transcript from a microfilm copy which was in his possession. The contents of the manuscript more than fulfilled expectation, for it appeared that the main theme was the computation of meridional parts for drawing a Mercator chart and, as Mr. Sadler, the Superintendent of H.M. Nautical Almanac Office, shows in the second part of this paper, Hariot was remarkably in advance of his time in his mathematical treatment of this problem, which continued to be a favourite one for discussion until the discovery of the calculus. As is well known, the first table of meridional parts to be published was that compiled (by simple addition of secants) by Edward Wright (1558–1615) of Caius College, Cambridge, a mathematician who had been nautical adviser to the Earl of Cumberland, and on occasion to the Lord High Admiral himself.

Language holds many pitfalls for the unwary. A housewife picks up her iron, and so does the golfer: a butcher uses the steel and so does the soldier: a government nationalizes iron and steel. No wonder the foreigner makes ludicrous mistakes. And we in our turn, coming across an Italian book entitled Il Compasso da Navigare might be pardoned for supposing its subject-matter to be the navigating compass. This is not so. It is a learned and comprehensive treatise under the title belonging to the oldest surviving Sailing Directions for the Mediterranean Sea, and as the author, Bacchisio R. Motzo, clearly proves, such Directions were called a Compasso, and by a natural transference the same name was given to the sailing chart which was drawn to accompany the Directions. What we call a mariner's compass, or simply a compass, the Italians term Compasso-bussola or more usually just bussola. When English sailors began to use written Directions or ‘Pilots’ they called them Rutters (from the French Routier), while an alternative Italian name for a Compasso was Portolano, which also meant the accompanying chart.

(1928). Pactolus: River of gold. Scottish Geographical Magazine: Vol. 44, No. 3, pp. 129-144.

(1935). Perfidious Albion: Climate and character in the sixteenth and seventeenth centuries. Scottish Geographical Magazine: Vol. 51, No. 1, pp. 1-6.

Four steps to Longitude! If we chose, we might interpret the phrase by a sequence of four names: Ptolemy, Charles II, Tobias Mayer and Nevil Maskelyne—the last in 1763. But in fact the steps represent the four marine timepieces made by John Harrison—familiarly known as H1, H2, H3 and H4 of which the last proved its efficacy in 1762. The longitude was found, and by a ‘machine’, just two centuries ago. Now the bi-centenary is being celebrated by a very elegant and informative exhibition at the National Maritime Museum, Greenwich. No navigator should miss it. Even if he thinks scorn of ‘ancient history’ he owes the inventor of the first English chronometer a tribute of respect.

CAPTAIN JAMES COOK is deservedly esteemed as a great seaman, and he must be acclaimed also in the more particular role of a great navigator. For although he made no specific contribution to the art of navigation as such, he advanced it by sheer force of character. It was, indeed, a task for the mathematicians and astronomers, not for the sailors, to lay down new principles and new observations or calculations by which a ship's position could be found and her course directed when at sea. And it was for the mathematical and optical instrument-makers to design and perfect the instruments by which such observations could be made. But, in the last resort, everything depended upon the ships' captains, the masters and the pilots. They alone could decide whether some novel principle should be mastered, some new instrument actually used. ‘We have piped unto you and ye have not danced’ is a cry which echoes through the ages. For the sailor was not alone in turning a deaf ear to the advice of public men, scientists and his own professional instructors. He was hostile to change, he preferred some old rule of thumb. And this is to be expected from all such men as learn the actual practice of their trade or craft by working beside an experienced master who in turn is passing on the traditions of an earlier generation.

In his detailed and valuable account of the history of the Log (this Journal, 9, 70) Commander Waters is surely at fault as regards the part he ascribes to the Gresham Professor, Gunter. This eminent mathematician delighted in designing instruments with engraved scales, and at first issued the customary Description and Use in Latin, a sufficient indication that he wrote only for fellow scholars. Importuned probably by the instrument-makers, he later published English versions of the tracts (in 1623), and among the numerous ‘uses’ included a couple of chapters on those for navigational purposes.

There are still people who believe that only during the last four-hundred years have we known that the Earth is a globe. They were taught this at school when they were told the story of Christopher Columbus. Columbus, it was said, went to King John of Portugal with the proposal to reach the fabulously rich Cathay, situated in the Far East, by sailing across the Atlantic Ocean to the west. The king consulted a committee of mathematicians who rejected the idea with scorn. The Earth was round and flat like a trencher, they said, and not a globe as Columbus maintained. And some teachers added that not until the circumnavigation of Magellan's ship, Victoria, was there any proof of the shape of the Earth.

How did Francis Drake navigate his ship when in 1577 he embarked upon his famous voyage round the world ? Strictly speaking he did not navigate her, for the task was delegated to subordinate officers. The Pelican (or Golden Hind as she was later renamed) carried, as was customary, a master and a pilot whose duty it was to make the necessary observations and lay the ship upon her course. But these had signed on for a supposed voyage to Alexandria to load currants, and Drake knew well enough that no English pilot could then compare with a pilot of Spain or Portugal, whether in training, experience or equipment: for these nations, as pioneers of the Great Discoveries, had also taken the lead in the development of nautical science and in the formal schooling of seamen. That explains why Captain Francis furnished himself with the latest chart from Lisbon, and why, when he reached African waters, he kidnapped a Portuguese pilo to sail him into the Pacific, only to maroon the unfortunate man in Central America when he had served his turn and a Spaniard was indicated for the next stage of the voyage. Hitherto no English ship had left the Atlantic, and apart from a few men trained in the Muscovy Company's service the average English sailor laughed at the idea of navigating with charts and instruments. He had his compass, he knew his landmarks, and once he was in soundings he could cast the lead and feel his way into harbour blindfold. To see a man ‘shooting the Sun’ (as it was already termed) with a cross-staff was an occasion for mockery. ‘Have you strook it?’ he would cry, ‘Have you strook it?’ And as for charts, he wanted none of your sheepskins, he could make his voyage as well upon a board! It was upon a prepared sheepskin that the mediaeval charts were drawn and painted, the neck to the left, while the ‘board’ was the traverse-board marked with the thirty-two rhumbs. These were pierced with holes at regular intervals, into which pegs were inserted at each turn of the sand-glass, thus recording the time sailed on any particular point of the compass.

There is rich material for studying navigation technique in the fifteenth and early sixteenth centuries in the volume A Marinharia dos Descobrimentos by the late Fontoura da Costa, which deals in great detail with the evidence for early sailing methods; the facsimile reprints of rare documents bearing on early Portuguese navigation lately published by Joaquim Bensaude for the Portuguese Government also contain much information on this period. The object of this article is two-fold: to establish that in an Addendum to one of these documents, the Reportorio dos Tempos of Valentim Fernandez (1st edition 1518), we have extracts from an archaic type of navigating manual; and hence to argue that, judging from his own words, Columbus (whose skill in navigation is a matter of controversy) had studied rules and instructions for navigation just such as the Addendum contains, but that owing to his lack of elementary mathematical training he had only imperfectly understood them.

English sailors came more than half a century late into the world of transatlantic voyages and new discoveries. Nor should this surprise us when we remember the exasperating delays they had to expect when getting out of our long river estuaries into the narrow seas, and out of the narrow seas into the Atlantic Ocean. Once there they still had to encounter prevailing head-winds, where a Columbus had only to launch himself on the steady trade winds to discover America.

New ideas of a really fundamental character are always received with horror and alarm by the general public, and are vigorously repudiated. When Fred Hoyle, in a brilliant series of broadcasts, remarked that his physico-mathematical calculations indicated that newly created hydrogen was being continuously injected into the Universe, the B.B.C. had to take hasty countermeasures. A well-known authoress of detective stories and religious pl ys, followed by a respected professor of science, declared on the air that the earlier t lks had been merely speculative. A similar role was filled in 1543 by the theologian Andreas Osiander, who added a Preface to Copernicus's startling book De Revolutionibus Orbium Coelestium (the author having just died), to the effect that he had only intended as a mathematical hypothesis, not as a matter of fact, to picture a rotating globe revolving round the Sun. From the point of view of pure geometry it was, it is true, merely a matter of a change of coordinates. People settled back comfortably for another sixty or seventy years, until Galileo made certain awkward observations with his new telescope.

A country that frowns on rich men must be content to let its rare books cross the ocean. Certainly it will lose all those which make no appeal to the literary man, and those to which the devotee of ‘pure’ science is indifferent, since these are the two groups who might be consulted before such a transference, or whose protests would be listened to. Hence it is that, because only a tiny minority has as yet been interested in the crude beginnings of applied science and technology, a discerning American member of the Institute, Mr. Henry C. Taylor, has formed a collection of about one hundred and fifty books which tell the story of how skippers and pilots were taught to set course and make port during the Great Age of Discovery and Colonization. Nearly half of these books are in English, and this is understandable, for although the pioneers of the new methods of navigation were the Portuguese, the English sailor took pride of place after the defeat of the Spanish Armada. Mr. Taylor appears at one time to have been satisfied with the breezy statement of Captain Smith of Virginia in 1626 that the seaman was sufficiently equipped if he had his Almanack, his Waggoner, a manual or two, and knew a good instrument-maker like Master Bates on Tower Hill. But one book leads to another, and, having got together these half-dozen books, he began to study them.

The sailor will not be kept from the sea, even though empires fall and foreign invaders multiply. Yet we cannot expect to hear much of him in such troubled times. We know, however, that although European ships no longer sailed to India, yet, after the barbarian destruction of the Roman Empire, overseas trade did revive, and the foundations of such famous maritime states as Venice were laid. We know, too, that although the Arabs overran the whole length of the Mediterranean Sea, they were pushed back out of the islands by sea-borne expeditions from Italy and Catalan Spain, while when the Holy Places in Palestine were captured by the Turks (who were not ‘gentlemen’ like the Arabs), there were ships and sailors ready and able to carry crusading armies to the East, and to provision them while they were there.

Sailors as a class may fairly claim to have been the earliest technicians; they were the first, that is to say, to graduate from the stage of simple craftsmanship, involving only the use of tools and rules of thumb, to the employment of instruments and mathematics for solving their problems. For the nautical chart and magnetic compass are instruments of precision while sailing directions, if they are to be useful, must be couched in mathematical language. All these three aids to navigation go back at least seven hundred years, and an Italian ship inventory of 1294 has been quoted which included two charts, a pair of compasses and two lodestones with their accompaniments.

That a ship's captain may exercise supreme powers when at sea has been recognized since maritime laws were first formulated. But when Francis Drake summarily executed Thomas Doughty in Patagonia in 1578 there were serious misgivings at home, and the commanding officer of the next long distance expedition was hedged about with carefully thought out restrictions, and ordered, save ia the last resort, to bring any serious offender home as a prisoner. This voyage was organized and financed by the Earl of Leicester, Drake and a number of City merchants, its objective being to open up trade with the Far East by a voyage round the Cape. It had originally been intended to put Martin Frobisher in command, but for reasons unknown a gentleman and soldier of fortune, who had been with him on the second and third voyages to the Northwest Passage, Captain Edward Fenton, was substituted for Frobisher. This caused murmuring among the sailors who evidently thought poorly of him. And he did indeed turn out a weak, vacillating leader, though full of his own importance, so that the voyage was a failure, and two of his ships actually left him.

The year 1952 is the fourth centenary of the birth of Sir Walter Ralegh. So far from being the great romantic of tradition Sir Walter was a hard-headed practical man, and the first Englishman to engage a scientific and technical expert to advise him on his colonizing enterprises. He brought the brilliant young mathematician Thomas Hariot, some eight years his junior, direct from Oxford to Durham House, his mansion in the Strand, where, setting his instruments up on the leads, Hariot laboured for years at improving observational technique and revising the Ephemerides. Meanwhile he gave instruction in navigation to the officers of Ralegh's ships, himself obtaining practical experience on the voyage to Virginia in 1585, when he was able to observe the seaman's difficulties and the errors to which he was prone. He had already by 1584 written a new Instruction Manual which he entitled Arcticon, but this is unfortunately lost. We have, nevertheless, an epitome of its contents, for Ralegh asked for a ‘refresher course’ on the eve of his departure for Guiana, which was to take place in February 1595, and Hariot's teaching notes in his own (very crabbed) handwriting, besides fair copies of the tables he drew up, are now at the British Museum.

(1933). John Taylor the water-poet and the transport problems of the early stuart period. Scottish Geographical Magazine: Vol. 49, No. 3, pp. 129-138.

(1927). The earliest account of triangulation. Scottish Geographical Magazine: Vol. 43, No. 6, pp. 341-345.