Whenever I upload a following program I am getting error message 
    showing"expected initializer before interval".
    Kindly Help me to solve out this probleme.






    const byte button=2;
    const byte LED=10;
    bool blinking =false;//defines when blinking should occur
    unsigned long blink Interval=250;// number of milliseconds for blink
    unsigned long currentMillis;// variables to track millis()
    unsigned long previousMillis;
    void setup() {
    pinMode (button,INPUT);
    pinMode (LED,OUTPUT);
    }
    void loop() {
    // this code  blinks the LED
    if (blinking) {
    currentMillis =millis();// better to store in variable, for less jitter
    if ((unsignedlong)(currentMillis-previousMillis) >=blinkInterval) {// enough time passed yet?
    digitalWrite (LED,!digitalRead(LED));// shortcut to toggle the LED
    previousMillis =currentMillis;// sets the time we wait "from"
    }
    } else{
    digitalWrite (LED,LOW);// force LED off when not blinking
    }
    int reading=digitalRead(button);
    delay (50);// crude de-bouncing
    if (reading==LOW)// buttons with pull-up are pressed when LOW
    blinking =true;// start blinking
    else
    blinking =false;// stop blinking
    }

Whenever I upload the following program I am getting error message showing "expected initializer before interval".

Kindly Help me to solve out this probleme.

const byte button=2;
const byte LED=10;
bool blinking =false;//defines when blinking should occur
unsigned long blink Interval=250;// number of milliseconds for blink
unsigned long currentMillis;// variables to track millis()
unsigned long previousMillis;
void setup() 
{
    pinMode(button,INPUT);
    pinMode(LED,OUTPUT);
}
void loop() 
{
    // this code  blinks the LED
    if(blinking) {
        currentMillis =millis();// better to store in variable, for less jitter 

        if((unsignedlong)(currentMillis-previousMillis) >=blinkInterval) { // enough time passed yet?
            digitalWrite(LED,!digitalRead(LED)); // shortcut to toggle the LED
            previousMillis =currentMillis;// sets the time we wait "from"
        }
    } else {
        digitalWrite(LED,LOW); // force LED off when not blinking
    } 

    int reading=digitalRead(button);
    delay(50); // crude de-bouncing 

    if(reading==LOW) // buttons with pull-up are pressed when LOW
    { blinking =true; }// start blinking
    else
    { blinking =false; }// stop blinking
}