Verner's law described a historical sound change in the Proto-Germanic language whereby consonants that would have been the voiceless fricatives *f, *þ, *s, *h, *hʷ, following an unstressed syllable, became the voiced fricatives *β, *ð, *z, *ɣ, *ɣʷ. The law was formulated by Karl Verner, first published in 1877. A seminal insight into how the Germanic languages diverged from their Indo-European ancestor had been established in the early nineteenth century, had been formulated as Grimm's law. Amongst other things, Grimm's law described how the Proto-Indo-European voiceless stops *p, *t, *k, *kʷ changed into Proto-Germanic *f, *þ, *h, *hʷ. However, there appeared to be a large set of words in which the agreement of Latin, Sanskrit, Slavic etc. guaranteed Proto-Indo-European *p, *t or *k, yet the Germanic reflex was not the expected, unvoiced fricatives *f, *þ, *h, *hʷ but rather their voiced counterparts *β, *ð, *ɣ, *ɣʷ. A similar problem obtained with Proto-Indo-European *s, which sometimes appeared as Proto-Germanic *z.

At first, irregularities did not cause concern for scholars since there were many examples of the regular outcome. However, it became the ambition of linguists like the Neogrammarians to formulate general and exceptionless rules of sound change that would account for all the data, not for a well-behaved subset of it. One classic example of Proto-Indo-European *t → Proto-Germanic *d is the word for'father'. Proto-Indo-European *ph₂tḗr → Proto-Germanic *faðēr. In the structurally similar family term bʰréh₂tēr'brother', Proto-Indo-European *t did indeed develop as predicted by Grimm's Law. More curiously, scholars found both *þ and *d as reflexes of Proto-Indo-European *t in different forms of one and the same root, e.g. *werþaną'to turn', preterite third-person singular *warþ'he turned', but preterite third-person plural *wurdun and past participle *wurdanaz. Karl Verner is traditionally credited as the first scholar to note the factor governing the distribution of the two outcomes. Verner observed that the unexpected voicing of Proto-Indo-European voiceless stops occurred if they were non-word-initial and if the vowel preceding them carried no stress in Proto-Indo-European.

The original location of stress was retained in Greek and early Sanskrit. The following table illustrates the sound changes according to Verner. In the bottom row, for each pair, the sound on the right represents the sound changed according to Verner's Law; the crucial difference between *patḗr and *bʰrā́tēr was therefore one of second-syllable versus first-syllable stress. The *werþaną: *wurdun contrast is explained as due to stress on the root versus stress on the inflectional suffix. There are other Vernerian alternations, as illustrated by modern German ziehen'to draw, pull': Old High German zogōn'to tug, drag' ← Proto-Germanic *teuhaną: *tugōną ← Pre-Germanic *déwk-o-nom: *duk-éh₂-yo-nom'lead'; the change described by Verner's Law accounts for Proto-Germanic *z as the development of Proto-Indo-European *s in some words. Since this *z changed to *r in the Scandinavian languages and in West Germanic, Verner's Law resulted in alternation of *s and *r in some inflectional paradigms, known as grammatischer Wechsel.

For example, the Old English verb ceosan'choose' had the past plural form curon and the past participle coren. These three forms derived from Proto-Germanic *keusaną: *kuzun ~ *kuzanaz, which again derived from Pre-Germanic *géws-o-nom: *gus-únt ~ *gus-o-nós'taste, try'. We would have **chorn for chosen in Modern English if the consonantal shell of choose and chose had not been morphologically levelled. On the other hand, Vernerian *r has not been levelled out in English were ← Proto-Germanic *wēzun, related to English was. English lose, though it has the weak form lost has the archaic form †lorn. Whereas the North Germanic and West Germanic languages show the effects of Verner's law, those patterns appear in Gothic, the representative of East Germanic; this is thought to be because Gothic eliminated most Verner's law variants through analogy with the unaffected consonants. Karl Verner published his discovery in the article "Eine Ausnahme der ersten Lautverschiebung" in Kuhn's Journal of Comparative Linguistic Research in 1877, but he had presented his theory on 1 May 1875 in a comprehensive personal letter to his friend and mentor, Vilhelm Thomsen.

A letter shows that Eduard Sievers did not publish it. Verner's theory was received with great enthusiasm by the young generation of comparative philologists, the so-called Junggrammatiker, because it was an important argument in favour of the Neogrammarian dogma that the sound laws were without exceptions; the change in pronunciation described by Verner's Law must have occurred before the shift of stress to the first syllable: the voicing of the new consonant in Proto-Germanic is conditioned by which syllable is stressed in Proto-Indo-European

The northwesternmost point of the Lake of the Woods was a critical landmark for the boundary between U. S. territory and the British possessions to the north. This point was referred to in the Treaty of Paris in 1783 and in treaties including the Treaty of 1818; this point lies at the corner of the Northwest Angle of Minnesota and is thus the northernmost point in the lower 48 United States. After Canadian Confederation, the point became the basis for the border between Manitoba and Ontario; the "northwesternmost point" of the lake had not yet been identified when it was referenced in treaties defining the border between the US and Britain. The best maps at the time of the original negotiation depicted the lake as a simple oval. However, although the southern portion of the lake is mapped, to the north it becomes a complex tangle of bays and islands, with many adjacent bodies of water separated or connected by narrow isthmuses or straits. An 1822 survey crew declared the referenced point impossible to determine.

In 1824, British explorer David Thompson was hired to identify it. Thompson mapped the lake and found four possibilities, but did not conclusively declare one location. In 1825, German astronomer in British service Dr. Johann Ludwig Tiarks surveyed the lake. Tiarks identified two possibilities for the northwesternmost point on the lake, based on Thompson's maps: the Angle Inlet and Rat Portage. To determine which point was the most northwestern, he drew a line from each point in the southwest-northeast direction. If the line intersected the lake at any point, it was not the most northwestern point, as shown in the example diagram here. Tiarks determined that the only such line that did not intersect the lake was at the edge of a pond on the Angle Inlet. Under the 1783 treaty, the international border would have run due west from this point to the Mississippi River; as this was determined to be geographically impossible, under the 1818 treaty the international border instead ran from the point determined by Tiarks, to the 49th parallel.

From there it ran due west to the Rocky Mountains. Tiarks' point, created problems, because the 1818 treaty called for the border to run directly north–south from it. South of that point, the channel of the Northwest Angle Inlet meandered east and west, crossing the border five times, thereby creating two small enclaves of water areas totaling two and a half acres that belonged to the United States but were surrounded by Canadian waters. A 1925 treaty addressed this by adopting the southernmost of the points where the channel and the border intersected – 5,000 ft south of Tiarks' point – as the new "northwesternmost point"; the new northwesternmost point thus became 49°23′4.14″N 95°9′11.34″W, based on the NAD27 datum, equivalent to 49°23′4.12373″N 95°9′12.20783″W under the modern NAD83 datum

The 336th Air Refueling Squadron is a United States Air Force Reserve squadron, assigned to the 452d Operations Group, stationed at March Joint Air Reserve Base, California. The squadron shares its aircraft and facility with the 912th Air Refueling Squadron, a USAF Associate Unit assigned to the 92d Air Refueling Wing; the first predecessor of the squadron was active during World War II. It served as a training unit in the southwestern United States before being inactivated in 1944 during a reorganization of the Army Air Force's training units; the second predecessor of the squadron was organized in the [[military reserve force|reserve\ in 1949 as the 336th Troop Carrier Squadron. The squadron operates the Boeing KC-135 Stratotanker aircraft conducting air refueling missions; the first predecessor of the squadron is the 536th Bombardment Squadron, activated at Salt Lake City Army Air Base in November 1942 as one of the four original squadrons of the 382d Bombardment Group. The squadron moved to Davis–Monthan Field, Arizona in January 1943 and began to operate as an Operational Training Unit for Consolidated B-24 Liberator units.

The OTU program involved the use of an oversized parent unit to provide cadres to "satellite groups". In April 1943, the squadron moved to Pocatello Army Air Field, where its mission changed to acting as a Replacement Training Unit for Liberator aircrews. RTUs were oversized units, but their mission was to train individual pilots or aircrews. However, the Army Air Forces was finding that standard military units like the 536th, based on inflexible tables of organization were not well adapted to the training mission. Accordingly the AAF adopted a more functional system in which each base was organized into a separate numbered unit, whose manning and equipment was tailored to the base's mission; as a result of this reorganization, the 536th was inactivated, along with other units at Muroc Army Air Field, replaced by the 421st AAF Base Unit. The second predecessor of the squadron was organized in the reserves as the 336th Troop Carrier Squadron at Birmingham Municipal Airport, Alabama in June 1949, although it moved to Mitchel Air Force Base, New York in October along with its parent 514th Troop Carrier Group.

At Mitchel, it trained under the supervision of Continental Air Command's 2233d Air Force Reserve Flying Training Center. The 514th Group was equipped with Curtiss C-46 Commandos during this period, but it is not clear if any of the group's operational aircraft were assigned to the squadron. All reserve combat units were mobilized for the Korean War; the squadron was mobilized on 1 May 1951, Its parent 514th Troop Carrier Wing was one of six C-46 wings were mobilized for Tactical Air Command and assigned to Eighteenth Air Force. The squadron remained at Mitchel and performed airlift missions until relieved from active duty on 1 February 1953; the squadron's personnel and equipment were transferred to the 47th Troop Carrier Squadron, activated at Mitchel the same day. The reserve began to receive aircraft again in July of 1952. While the squadron was still serving on active duty, ConAC had formed the 65th Troop Carrier Wing at Mitchel in 1952 as a reserve airlift unit. On 1 April 1953, the 514th Wing returned to the reserves, replacing the 65th Wing, the 336th Squadron was activated and absorbed the personnel and equipment of the 13th Troop Carrier Squadron.

The squadron again trained with the 2233d Center, flying C-46 Commandos but it completed transition to Fairchild C-119 Flying Boxcars by August 1954. In the summer of 1956, the unit participated in Operation Sixteen Ton during its two weeks of active duty training. Sixteen Ton was performed by reserve troop carrier units and moved United States Coast Guard equipment From Floyd Bennett Naval Air Station, New York to Isla Grande Airport in Puerto Rico and San Salvador in the Bahamas. After the success of this operation, the squadron began to use inactive duty training periods for Operation Swift Lift, transporting high priority cargo for the Air Force and Operation Ready Swap, transporting aircraft engines between Air Materiel Command’s depots. In 1958, the 2233d Center was inactivated and some of its personnel were absorbed by the squadron. In place of active duty support for reserve units, ConAC adopted the Air Reserve Technician program, in which a cadre of the unit consisted of full-time personnel who were civilian employees of the Air Force and held military rank as members of the reserve.

After 1958, the squadron participated in humanitarian and other airlift missions. In April 1959, the 514th Wing reorganized under the Dual Deputy system, its 514th Troop Carrier Group was inactivated and the squadron was assigned directly to the wing. Starting in late 1955, Continental Air Command had begun to disperse some of its reserve flying squadrons to separate bases in order to improve recruiting and avoid public objection to entire wings of aircraft being stationed near large population centers under what was called the Detached Squadron Concept; the 336th Squadron moved to New York in March 1961 as part of this program. Although the dispersal of flying units was not a problem when the entire wing was called to active service, mobilizing a single flying squadron and elements to support it proved difficult; this weakness was demonstrated in the partial mobilization of reserve units during the Berlin Crisis of 1961 To resolve this, at the start of 1962, ConAC determined to reorganize its reserve wings by establishing groups with support elements for each of its troop carrier squadrons.

This reorganization would facilitate mobilization of elements of wings in various combinations when