From every quarter we hear ot strikes among mechanics, artizans, and laborers for an increase of wages. The operatives of eve'y trade, we believe, in the city of New York, together with waiters in hotels, coachmen, and laborers, have met in separate bodies, and have solicited an increase of wages. The movement is not confined to one city or State in our Republic, nor to our country itself. By the latest news from Europe we are informed ot a like movement going on among the operative classes in Britain. There must be a cause for this general and simultaneous movement. Those who demand an advance of wages, allege that necessity compels them to ask for it. They state " that provisions and house rents have greatly advanced within the past two years, and to enable them to meet the common exigencies of life, their wages must be advanced or they will suffer." No exception can be taken to the truthfulness ot these statements, but they do not giv us the exact information respecting the real cause ol this geneial movement for an increase of wages—the facts which they set forth for the necessity of an increase of wages are themselves but the effects of some cause. What is it ? In our opinion it is the great increase of gold and the vast amount of it which has been added to the currency or coinage of the world within two years. There have been no general failures in the earth's fruitage for a few years past. Stones, brick, lime, and timber, for constructing houses, require no greater labor now than has heretofore been employed to shape and fit them for common use. The land still remains where it was before, and there are millions of acres yet unoccupied.— But bread, beef, houses, and lands, have increased in price, and by what cause ? We believe- the cause to be a depreciation of the value of gold as eunent coin. The value of gold is only relative; that is, s its standard must be the amount of anything , else for which it can be exchanged. When it ] was less abundant more articles of another j kind could be had in exchange for it. There 1 was a time when our forefathers thought they were well paid when they received sixpence j for a day's wages. With that amount of what j we would call" small wages,' they could pur- ; chase more wheat and beef than we can do lor twenty times the same amount of money. The value of gold or any current coin then, is only to be measured by the amount of the necessaries of life (they really bound its value) for which it can be exchanged. With every inordinate increase in the quantity of gold, or any current coin, there must of necessity be a depreciation of its value. This, as we have stated, we hold to be the cause of the recent advances in the price of provisions and rents in our cities. We like to see every workman receive " a fair day's wages for a fair day's work." The more comfortable and respectable our people are universally, we certainly expect them to be more intelligent, happy, and moial. The wages of the operatives have in general been advanced in New York City, and we hope-this will be reciprocated by those who have been directly benefitted. There is, however, a general prevailing spirit in all classes, to sell dear and buy cheap; hence it is often found that those who pay low and sell cheap are patronized by the very persons who are continually declaiming against low pay themiaelves. If manufacturers advance the wages of the operatives, let the operators not grudge to pay a little more per yard for the cloth which they purchase. The interests of the employer and employed are not antassflistical, they should be considered by bothTparties as one. It is, however, very difficult to raise the price of any article in general use, which has for a long time maintained a fixed price. Thus, although a newspaper proprietor advances the wages of his compositors, no increase is made in the price of his paper, because, in all likeli- hood it would decrease in circulation, and yet who can doubt but the said proprietor is as much affected with the high prices ot which his workmen complain as they are themselves. As the Scientific American is " the advocate of Industry," it becomes us to notice such movements am/ng our operatives as the one we h*ave been expatiating upon. On another page will be found some statistics of the great increase of our gold coinage—an increase so large indeed that we cannot but look upon a general increase of prices in many things as a certain consequence.